Imagine a portable 3D printer you could hold in the palm of your hand. The tiny device could enable a user to rapidly create customized, low-cost objects on the go, like a fastener to repair a wobbly bicycle wheel or a component for a critical medical operation.

Researchers from MIT and the University of Texas at Austin took a major step toward making this idea a reality by demonstrating the first chip-based 3D printer. Their proof-of-concept device consists of a single, millimeter-scale photonic chip that emits reconfigurable beams of light into a well of resin that cures into a solid shape when light strikes it.

The prototype chip has no moving parts, instead relying on an array of tiny optical antennas to steer a beam of light. The beam projects up into a liquid resin that has been designed to rapidly cure when exposed to the beam’s wavelength of visible light.

By combining silicon photonics and photochemistry, the interdisciplinary research team was able to demonstrate a chip that can steer light beams to 3D print arbitrary two-dimensional patterns, including the letters M-I-T. Shapes can be fully formed in a matter of seconds.

In the long run, they envision a system where a photonic chip sits at the bottom of a well of resin and emits a 3D hologram of visible light, rapidly curing an entire object in a single step.

This type of portable 3D printer could have many applications, such as enabling clinicians to create tailor-made medical device components or allowing engineers to make rapid prototypes at a job site.

“This system is completely rethinking what a 3D printer is. It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable. It is exciting to think about the new applications that could come out of this and how the field of 3D printing could change,” says senior author Jelena Notaros, the Robert J. Shillman Career Development Professor in Electrical Engineering and Computer Science (EECS), and a member of the Research Laboratory of Electronics.

Joining Notaros on the paper are Sabrina Corsetti, lead author and EECS graduate student; Milica Notaros PhD ’23; Tal Sneh, an EECS graduate student; Alex Safford, a recent graduate of the University of Texas at Austin; and Zak Page, an assistant professor in the Department of Chemical Engineering at UT Austin. The research appears today in Nature Light Science and Applications.

Printing with a chip

Experts in silicon photonics, the Notaros group previously developed integrated optical-phased-array systems that steer beams of light using a series of microscale antennas fabricated on a chip using semiconductor manufacturing processes. By speeding up or delaying the optical signal on either side of the antenna array, they can move the beam of emitted light in a certain direction.

Such systems are key for lidar sensors, which map their surroundings by emitting infrared light beams that bounce off nearby objects. Recently, the group has focused on systems that emit and steer visible light for augmented-reality applications.

They wondered if such a device could be used for a chip-based 3D printer.

At about the same time they started brainstorming, the Page Group at UT Austin demonstrated specialized resins that can be rapidly cured using wavelengths of visible light for the first time. This was the missing piece that pushed the chip-based 3D printer into reality.

“With photocurable resins, it is very hard to get them to cure all the way up at infrared wavelengths, which is where integrated optical-phased-array systems were operating in the past for lidar,” Corsetti says. “Here, we are meeting in the middle between standard photochemistry and silicon photonics by using visible-light-curable resins and visible-light-emitting chips to create this chip-based 3D printer. You have this merging of two technologies into a completely new idea.”

Their prototype consists of a single photonic chip containing an array of 160-nanometer-thick optical antennas. (A sheet of paper is about 100,000 nanometers thick.) The entire chip fits onto a U.S. quarter.

When powered by an off-chip laser, the antennas emit a steerable beam of visible light into the well of photocurable resin. The chip sits below a clear slide, like those used in microscopes, which contains a shallow indentation that holds the resin. The researchers use electrical signals to nonmechanically steer the light beam, causing the resin to solidify wherever the beam strikes it.

A collaborative approach

But effectively modulating visible-wavelength light, which involves modifying its amplitude and phase, is especially tricky. One common method requires heating the chip, but this is inefficient and takes a large amount of physical space.

Instead, the researchers used liquid crystal to fashion compact modulators they integrate onto the chip. The material’s unique optical properties enable the modulators to be extremely efficient and only about 20 microns in length.

A single waveguide on the chip holds the light from the off-chip laser. Running along the waveguide are tiny taps which tap off a little bit of light to each of the antennas.

The researchers actively tune the modulators using an electric field, which reorients the liquid crystal molecules in a certain direction. In this way, they can precisely control the amplitude and phase of light being routed to the antennas.

But forming and steering the beam is only half the battle. Interfacing with a novel photocurable resin was a completely different challenge.

The Page Group at UT Austin worked closely with the Notaros Group at MIT, carefully adjusting the chemical combinations and concentrations to zero-in on a formula that provided a long shelf-life and rapid curing.

In the end, the group used their prototype to 3D print arbitrary two-dimensional shapes within seconds.

Building off this prototype, they want to move toward developing a system like the one they originally conceptualized — a chip that emits a hologram of visible light in a resin well to enable volumetric 3D printing in only one step.

“To be able to do that, we need a completely new silicon-photonics chip design. We already laid out a lot of what that final system would look like in this paper. And, now, we are excited to continue working towards this ultimate demonstration,” Jelena Notaros says.

This work was funded, in part, by the U.S. National Science Foundation, the U.S. Defense Advanced Research Projects Agency, the Robert A. Welch Foundation, the MIT Rolf G. Locher Endowed Fellowship, and the MIT Frederick and Barbara Cronin Fellowship.

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

Imagine a portable 3D printer you could hold in the palm of your hand. The tiny device could enable a user to rapidly create customized, low-cost objects on the go, like a fastener to repair a wobbly bicycle wheel or a component for a critical medical operation.

Researchers from MIT and the University of Texas at Austin took a major step toward making this idea a reality by demonstrating the first chip-based 3D printer. Their proof-of-concept device consists of a single, millimeter-scale photonic chip that emits reconfigurable beams of light into a well of resin that cures into a solid shape when light strikes it.

The prototype chip has no moving parts, instead relying on an array of tiny optical antennas to steer a beam of light. The beam projects up into a liquid resin that has been designed to rapidly cure when exposed to the beam’s wavelength of visible light.

By combining silicon photonics and photochemistry, the interdisciplinary research team was able to demonstrate a chip that can steer light beams to 3D print arbitrary two-dimensional patterns, including the letters M-I-T. Shapes can be fully formed in a matter of seconds.

In the long run, they envision a system where a photonic chip sits at the bottom of a well of resin and emits a 3D hologram of visible light, rapidly curing an entire object in a single step.

This type of portable 3D printer could have many applications, such as enabling clinicians to create tailor-made medical device components or allowing engineers to make rapid prototypes at a job site.

“This system is completely rethinking what a 3D printer is. It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable. It is exciting to think about the new applications that could come out of this and how the field of 3D printing could change,” says senior author Jelena Notaros, the Robert J. Shillman Career Development Professor in Electrical Engineering and Computer Science (EECS), and a member of the Research Laboratory of Electronics.

Joining Notaros on the paper are Sabrina Corsetti, lead author and EECS graduate student; Milica Notaros PhD ’23; Tal Sneh, an EECS graduate student; Alex Safford, a recent graduate of the University of Texas at Austin; and Zak Page, an assistant professor in the Department of Chemical Engineering at UT Austin. The research appears today in Nature Light Science and Applications.

Printing with a chip

Experts in silicon photonics, the Notaros group previously developed integrated optical-phased-array systems that steer beams of light using a series of microscale antennas fabricated on a chip using semiconductor manufacturing processes. By speeding up or delaying the optical signal on either side of the antenna array, they can move the beam of emitted light in a certain direction.

Such systems are key for lidar sensors, which map their surroundings by emitting infrared light beams that bounce off nearby objects. Recently, the group has focused on systems that emit and steer visible light for augmented-reality applications.

They wondered if such a device could be used for a chip-based 3D printer.

At about the same time they started brainstorming, the Page Group at UT Austin demonstrated specialized resins that can be rapidly cured using wavelengths of visible light for the first time. This was the missing piece that pushed the chip-based 3D printer into reality.

“With photocurable resins, it is very hard to get them to cure all the way up at infrared wavelengths, which is where integrated optical-phased-array systems were operating in the past for lidar,” Corsetti says. “Here, we are meeting in the middle between standard photochemistry and silicon photonics by using visible-light-curable resins and visible-light-emitting chips to create this chip-based 3D printer. You have this merging of two technologies into a completely new idea.”

Their prototype consists of a single photonic chip containing an array of 160-nanometer-thick optical antennas. (A sheet of paper is about 100,000 nanometers thick.) The entire chip fits onto a U.S. quarter.

When powered by an off-chip laser, the antennas emit a steerable beam of visible light into the well of photocurable resin. The chip sits below a clear slide, like those used in microscopes, which contains a shallow indentation that holds the resin. The researchers use electrical signals to nonmechanically steer the light beam, causing the resin to solidify wherever the beam strikes it.

A collaborative approach

But effectively modulating visible-wavelength light, which involves modifying its amplitude and phase, is especially tricky. One common method requires heating the chip, but this is inefficient and takes a large amount of physical space.

Instead, the researchers used liquid crystal to fashion compact modulators they integrate onto the chip. The material’s unique optical properties enable the modulators to be extremely efficient and only about 20 microns in length.

A single waveguide on the chip holds the light from the off-chip laser. Running along the waveguide are tiny taps which tap off a little bit of light to each of the antennas.

The researchers actively tune the modulators using an electric field, which reorients the liquid crystal molecules in a certain direction. In this way, they can precisely control the amplitude and phase of light being routed to the antennas.

But forming and steering the beam is only half the battle. Interfacing with a novel photocurable resin was a completely different challenge.

The Page Group at UT Austin worked closely with the Notaros Group at MIT, carefully adjusting the chemical combinations and concentrations to zero-in on a formula that provided a long shelf-life and rapid curing.

In the end, the group used their prototype to 3D print arbitrary two-dimensional shapes within seconds.

Building off this prototype, they want to move toward developing a system like the one they originally conceptualized — a chip that emits a hologram of visible light in a resin well to enable volumetric 3D printing in only one step.

“To be able to do that, we need a completely new silicon-photonics chip design. We already laid out a lot of what that final system would look like in this paper. And, now, we are excited to continue working towards this ultimate demonstration,” Jelena Notaros says.

This work was funded, in part, by the U.S. National Science Foundation, the U.S. Defense Advanced Research Projects Agency, the Robert A. Welch Foundation, the MIT Rolf G. Locher Endowed Fellowship, and the MIT Frederick and Barbara Cronin Fellowship.

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

A new technical paper titled “Mechanically-flexible wafer-scale integrated-photonics fabrication platform” was published by researchers at MIT and New York Center for Research, Economic Advancement, Technology, Engineering, and Science (NY CREATES).

Abstract
“The field of integrated photonics has advanced rapidly due to wafer-scale fabrication, with integrated-photonics platforms and fabrication processes being demonstrated at both infrared and visible wavelengths. However, these demonstrations have primarily focused on fabrication processes on silicon substrates that result in rigid photonic wafers and chips, which limit the potential application spaces. There are many application areas that would benefit from mechanically-flexible integrated-photonics wafers, such as wearable healthcare monitors and pliable displays. Although there have been demonstrations of mechanically-flexible photonics fabrication, they have been limited to fabrication processes on the individual device or chip scale, which limits scalability. In this paper, we propose, develop, and experimentally characterize the first 300-mm wafer-scale platform and fabrication process that results in mechanically-flexible photonic wafers and chips. First, we develop and describe the 300-mm wafer-scale CMOS-compatible flexible platform and fabrication process. Next, we experimentally demonstrate key optical functionality at visible wavelengths, including chip coupling, waveguide routing, and passive devices. Then, we perform a bend-durability study to characterize the mechanical flexibility of the photonic chips, demonstrating bending a single chip 2000 times down to a bend diameter of 0.5 inch with no degradation in the optical performance. Finally, we experimentally characterize polarization-rotation effects induced by bending the flexible photonic chips. This work will enable the field of integrated photonics to advance into new application areas that require flexible photonic chips.”

Find the technical paper here. Published May 2024. Find MIT’s news release here.

Notaros, M., Dyer, T., Garcia Coleto, A. et al. Mechanically-flexible wafer-scale integrated-photonics fabrication platform. Sci Rep 14, 10623 (2024). https://doi.org/10.1038/s41598-024-61055-w.

The post Flexible-Wafer Platform And CMOS-Compatible 300mm Wafer-Scale Integrated-Photonics Fabrication appeared first on Semiconductor Engineering.

Imagine a portable 3D printer you could hold in the palm of your hand. The tiny device could enable a user to rapidly create customized, low-cost objects on the go, like a fastener to repair a wobbly bicycle wheel or a component for a critical medical operation.

Researchers from MIT and the University of Texas at Austin took a major step toward making this idea a reality by demonstrating the first chip-based 3D printer. Their proof-of-concept device consists of a single, millimeter-scale photonic chip that emits reconfigurable beams of light into a well of resin that cures into a solid shape when light strikes it.

The prototype chip has no moving parts, instead relying on an array of tiny optical antennas to steer a beam of light. The beam projects up into a liquid resin that has been designed to rapidly cure when exposed to the beam’s wavelength of visible light.

By combining silicon photonics and photochemistry, the interdisciplinary research team was able to demonstrate a chip that can steer light beams to 3D print arbitrary two-dimensional patterns, including the letters M-I-T. Shapes can be fully formed in a matter of seconds.

In the long run, they envision a system where a photonic chip sits at the bottom of a well of resin and emits a 3D hologram of visible light, rapidly curing an entire object in a single step.

This type of portable 3D printer could have many applications, such as enabling clinicians to create tailor-made medical device components or allowing engineers to make rapid prototypes at a job site.

“This system is completely rethinking what a 3D printer is. It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable. It is exciting to think about the new applications that could come out of this and how the field of 3D printing could change,” says senior author Jelena Notaros, the Robert J. Shillman Career Development Professor in Electrical Engineering and Computer Science (EECS), and a member of the Research Laboratory of Electronics.

Joining Notaros on the paper are Sabrina Corsetti, lead author and EECS graduate student; Milica Notaros PhD ’23; Tal Sneh, an EECS graduate student; Alex Safford, a recent graduate of the University of Texas at Austin; and Zak Page, an assistant professor in the Department of Chemical Engineering at UT Austin. The research appears today in Nature Light Science and Applications.

Printing with a chip

Experts in silicon photonics, the Notaros group previously developed integrated optical-phased-array systems that steer beams of light using a series of microscale antennas fabricated on a chip using semiconductor manufacturing processes. By speeding up or delaying the optical signal on either side of the antenna array, they can move the beam of emitted light in a certain direction.

Such systems are key for lidar sensors, which map their surroundings by emitting infrared light beams that bounce off nearby objects. Recently, the group has focused on systems that emit and steer visible light for augmented-reality applications.

They wondered if such a device could be used for a chip-based 3D printer.

At about the same time they started brainstorming, the Page Group at UT Austin demonstrated specialized resins that can be rapidly cured using wavelengths of visible light for the first time. This was the missing piece that pushed the chip-based 3D printer into reality.

“With photocurable resins, it is very hard to get them to cure all the way up at infrared wavelengths, which is where integrated optical-phased-array systems were operating in the past for lidar,” Corsetti says. “Here, we are meeting in the middle between standard photochemistry and silicon photonics by using visible-light-curable resins and visible-light-emitting chips to create this chip-based 3D printer. You have this merging of two technologies into a completely new idea.”

Their prototype consists of a single photonic chip containing an array of 160-nanometer-thick optical antennas. (A sheet of paper is about 100,000 nanometers thick.) The entire chip fits onto a U.S. quarter.

When powered by an off-chip laser, the antennas emit a steerable beam of visible light into the well of photocurable resin. The chip sits below a clear slide, like those used in microscopes, which contains a shallow indentation that holds the resin. The researchers use electrical signals to nonmechanically steer the light beam, causing the resin to solidify wherever the beam strikes it.

A collaborative approach

But effectively modulating visible-wavelength light, which involves modifying its amplitude and phase, is especially tricky. One common method requires heating the chip, but this is inefficient and takes a large amount of physical space.

Instead, the researchers used liquid crystal to fashion compact modulators they integrate onto the chip. The material’s unique optical properties enable the modulators to be extremely efficient and only about 20 microns in length.

A single waveguide on the chip holds the light from the off-chip laser. Running along the waveguide are tiny taps which tap off a little bit of light to each of the antennas.

The researchers actively tune the modulators using an electric field, which reorients the liquid crystal molecules in a certain direction. In this way, they can precisely control the amplitude and phase of light being routed to the antennas.

But forming and steering the beam is only half the battle. Interfacing with a novel photocurable resin was a completely different challenge.

The Page Group at UT Austin worked closely with the Notaros Group at MIT, carefully adjusting the chemical combinations and concentrations to zero-in on a formula that provided a long shelf-life and rapid curing.

In the end, the group used their prototype to 3D print arbitrary two-dimensional shapes within seconds.

Building off this prototype, they want to move toward developing a system like the one they originally conceptualized — a chip that emits a hologram of visible light in a resin well to enable volumetric 3D printing in only one step.

“To be able to do that, we need a completely new silicon-photonics chip design. We already laid out a lot of what that final system would look like in this paper. And, now, we are excited to continue working towards this ultimate demonstration,” Jelena Notaros says.

This work was funded, in part, by the U.S. National Science Foundation, the U.S. Defense Advanced Research Projects Agency, the Robert A. Welch Foundation, the MIT Rolf G. Locher Endowed Fellowship, and the MIT Frederick and Barbara Cronin Fellowship.

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

A new technical paper titled “Mechanically-flexible wafer-scale integrated-photonics fabrication platform” was published by researchers at MIT and New York Center for Research, Economic Advancement, Technology, Engineering, and Science (NY CREATES).

Abstract
“The field of integrated photonics has advanced rapidly due to wafer-scale fabrication, with integrated-photonics platforms and fabrication processes being demonstrated at both infrared and visible wavelengths. However, these demonstrations have primarily focused on fabrication processes on silicon substrates that result in rigid photonic wafers and chips, which limit the potential application spaces. There are many application areas that would benefit from mechanically-flexible integrated-photonics wafers, such as wearable healthcare monitors and pliable displays. Although there have been demonstrations of mechanically-flexible photonics fabrication, they have been limited to fabrication processes on the individual device or chip scale, which limits scalability. In this paper, we propose, develop, and experimentally characterize the first 300-mm wafer-scale platform and fabrication process that results in mechanically-flexible photonic wafers and chips. First, we develop and describe the 300-mm wafer-scale CMOS-compatible flexible platform and fabrication process. Next, we experimentally demonstrate key optical functionality at visible wavelengths, including chip coupling, waveguide routing, and passive devices. Then, we perform a bend-durability study to characterize the mechanical flexibility of the photonic chips, demonstrating bending a single chip 2000 times down to a bend diameter of 0.5 inch with no degradation in the optical performance. Finally, we experimentally characterize polarization-rotation effects induced by bending the flexible photonic chips. This work will enable the field of integrated photonics to advance into new application areas that require flexible photonic chips.”

Find the technical paper here. Published May 2024. Find MIT’s news release here.

Notaros, M., Dyer, T., Garcia Coleto, A. et al. Mechanically-flexible wafer-scale integrated-photonics fabrication platform. Sci Rep 14, 10623 (2024). https://doi.org/10.1038/s41598-024-61055-w.

The post Flexible-Wafer Platform And CMOS-Compatible 300mm Wafer-Scale Integrated-Photonics Fabrication appeared first on Semiconductor Engineering.

Imagine a portable 3D printer you could hold in the palm of your hand. The tiny device could enable a user to rapidly create customized, low-cost objects on the go, like a fastener to repair a wobbly bicycle wheel or a component for a critical medical operation.

Researchers from MIT and the University of Texas at Austin took a major step toward making this idea a reality by demonstrating the first chip-based 3D printer. Their proof-of-concept device consists of a single, millimeter-scale photonic chip that emits reconfigurable beams of light into a well of resin that cures into a solid shape when light strikes it.

The prototype chip has no moving parts, instead relying on an array of tiny optical antennas to steer a beam of light. The beam projects up into a liquid resin that has been designed to rapidly cure when exposed to the beam’s wavelength of visible light.

By combining silicon photonics and photochemistry, the interdisciplinary research team was able to demonstrate a chip that can steer light beams to 3D print arbitrary two-dimensional patterns, including the letters M-I-T. Shapes can be fully formed in a matter of seconds.

In the long run, they envision a system where a photonic chip sits at the bottom of a well of resin and emits a 3D hologram of visible light, rapidly curing an entire object in a single step.

This type of portable 3D printer could have many applications, such as enabling clinicians to create tailor-made medical device components or allowing engineers to make rapid prototypes at a job site.

“This system is completely rethinking what a 3D printer is. It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable. It is exciting to think about the new applications that could come out of this and how the field of 3D printing could change,” says senior author Jelena Notaros, the Robert J. Shillman Career Development Professor in Electrical Engineering and Computer Science (EECS), and a member of the Research Laboratory of Electronics.

Joining Notaros on the paper are Sabrina Corsetti, lead author and EECS graduate student; Milica Notaros PhD ’23; Tal Sneh, an EECS graduate student; Alex Safford, a recent graduate of the University of Texas at Austin; and Zak Page, an assistant professor in the Department of Chemical Engineering at UT Austin. The research appears today in Nature Light Science and Applications.

Printing with a chip

Experts in silicon photonics, the Notaros group previously developed integrated optical-phased-array systems that steer beams of light using a series of microscale antennas fabricated on a chip using semiconductor manufacturing processes. By speeding up or delaying the optical signal on either side of the antenna array, they can move the beam of emitted light in a certain direction.

Such systems are key for lidar sensors, which map their surroundings by emitting infrared light beams that bounce off nearby objects. Recently, the group has focused on systems that emit and steer visible light for augmented-reality applications.

They wondered if such a device could be used for a chip-based 3D printer.

At about the same time they started brainstorming, the Page Group at UT Austin demonstrated specialized resins that can be rapidly cured using wavelengths of visible light for the first time. This was the missing piece that pushed the chip-based 3D printer into reality.

“With photocurable resins, it is very hard to get them to cure all the way up at infrared wavelengths, which is where integrated optical-phased-array systems were operating in the past for lidar,” Corsetti says. “Here, we are meeting in the middle between standard photochemistry and silicon photonics by using visible-light-curable resins and visible-light-emitting chips to create this chip-based 3D printer. You have this merging of two technologies into a completely new idea.”

Their prototype consists of a single photonic chip containing an array of 160-nanometer-thick optical antennas. (A sheet of paper is about 100,000 nanometers thick.) The entire chip fits onto a U.S. quarter.

When powered by an off-chip laser, the antennas emit a steerable beam of visible light into the well of photocurable resin. The chip sits below a clear slide, like those used in microscopes, which contains a shallow indentation that holds the resin. The researchers use electrical signals to nonmechanically steer the light beam, causing the resin to solidify wherever the beam strikes it.

A collaborative approach

But effectively modulating visible-wavelength light, which involves modifying its amplitude and phase, is especially tricky. One common method requires heating the chip, but this is inefficient and takes a large amount of physical space.

Instead, the researchers used liquid crystal to fashion compact modulators they integrate onto the chip. The material’s unique optical properties enable the modulators to be extremely efficient and only about 20 microns in length.

A single waveguide on the chip holds the light from the off-chip laser. Running along the waveguide are tiny taps which tap off a little bit of light to each of the antennas.

The researchers actively tune the modulators using an electric field, which reorients the liquid crystal molecules in a certain direction. In this way, they can precisely control the amplitude and phase of light being routed to the antennas.

But forming and steering the beam is only half the battle. Interfacing with a novel photocurable resin was a completely different challenge.

The Page Group at UT Austin worked closely with the Notaros Group at MIT, carefully adjusting the chemical combinations and concentrations to zero-in on a formula that provided a long shelf-life and rapid curing.

In the end, the group used their prototype to 3D print arbitrary two-dimensional shapes within seconds.

Building off this prototype, they want to move toward developing a system like the one they originally conceptualized — a chip that emits a hologram of visible light in a resin well to enable volumetric 3D printing in only one step.

“To be able to do that, we need a completely new silicon-photonics chip design. We already laid out a lot of what that final system would look like in this paper. And, now, we are excited to continue working towards this ultimate demonstration,” Jelena Notaros says.

This work was funded, in part, by the U.S. National Science Foundation, the U.S. Defense Advanced Research Projects Agency, the Robert A. Welch Foundation, the MIT Rolf G. Locher Endowed Fellowship, and the MIT Frederick and Barbara Cronin Fellowship.

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

A technical paper titled “Programmable Nonlinear Quantum Photonic Circuits” was published by researchers at Niels Bohr Institute, University of Copenhagen, University of Bristol, and Ruhr-Universitat Bochum.

Abstract:

“The lack of interactions between single photons prohibits direct nonlinear operations in quantum optical circuits, representing a central obstacle in photonic quantum technologies. Here, we demonstrate multi-mode nonlinear photonic circuits where both linear and direct nonlinear operations can be programmed with high precision at the single-photon level. Deterministic nonlinear interaction is realized with a tunable quantum dot embedded in a nanophotonic waveguide mediating interactions between individual photons within a temporal linear optical interferometer. We demonstrate the capability to reprogram the nonlinear photonic circuits and implement protocols where strong nonlinearities are required, in particular for quantum simulation of anharmonic molecular dynamics, thereby showcasing the new key functionalities enabled by our technology.”

Find the technical paper here. Published May 2024 (preprint).

Nielsen, Kasper H., Ying Wang, Edward Deacon, Patrik I. Sund, Zhe Liu, Sven Scholz, Andreas D. Wieck et al. “Programmable Nonlinear Quantum Photonic Circuits.” arXiv preprint arXiv:2405.17941 (2024).

Related Reading
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The post Demonstrating Programmable Nonlinear Quantum Photonic ICs appeared first on Semiconductor Engineering.

Imagine a portable 3D printer you could hold in the palm of your hand. The tiny device could enable a user to rapidly create customized, low-cost objects on the go, like a fastener to repair a wobbly bicycle wheel or a component for a critical medical operation.

Researchers from MIT and the University of Texas at Austin took a major step toward making this idea a reality by demonstrating the first chip-based 3D printer. Their proof-of-concept device consists of a single, millimeter-scale photonic chip that emits reconfigurable beams of light into a well of resin that cures into a solid shape when light strikes it.

The prototype chip has no moving parts, instead relying on an array of tiny optical antennas to steer a beam of light. The beam projects up into a liquid resin that has been designed to rapidly cure when exposed to the beam’s wavelength of visible light.

By combining silicon photonics and photochemistry, the interdisciplinary research team was able to demonstrate a chip that can steer light beams to 3D print arbitrary two-dimensional patterns, including the letters M-I-T. Shapes can be fully formed in a matter of seconds.

In the long run, they envision a system where a photonic chip sits at the bottom of a well of resin and emits a 3D hologram of visible light, rapidly curing an entire object in a single step.

This type of portable 3D printer could have many applications, such as enabling clinicians to create tailor-made medical device components or allowing engineers to make rapid prototypes at a job site.

“This system is completely rethinking what a 3D printer is. It is no longer a big box sitting on a bench in a lab creating objects, but something that is handheld and portable. It is exciting to think about the new applications that could come out of this and how the field of 3D printing could change,” says senior author Jelena Notaros, the Robert J. Shillman Career Development Professor in Electrical Engineering and Computer Science (EECS), and a member of the Research Laboratory of Electronics.

Joining Notaros on the paper are Sabrina Corsetti, lead author and EECS graduate student; Milica Notaros PhD ’23; Tal Sneh, an EECS graduate student; Alex Safford, a recent graduate of the University of Texas at Austin; and Zak Page, an assistant professor in the Department of Chemical Engineering at UT Austin. The research appears today in Nature Light Science and Applications.

Printing with a chip

Experts in silicon photonics, the Notaros group previously developed integrated optical-phased-array systems that steer beams of light using a series of microscale antennas fabricated on a chip using semiconductor manufacturing processes. By speeding up or delaying the optical signal on either side of the antenna array, they can move the beam of emitted light in a certain direction.

Such systems are key for lidar sensors, which map their surroundings by emitting infrared light beams that bounce off nearby objects. Recently, the group has focused on systems that emit and steer visible light for augmented-reality applications.

They wondered if such a device could be used for a chip-based 3D printer.

At about the same time they started brainstorming, the Page Group at UT Austin demonstrated specialized resins that can be rapidly cured using wavelengths of visible light for the first time. This was the missing piece that pushed the chip-based 3D printer into reality.

“With photocurable resins, it is very hard to get them to cure all the way up at infrared wavelengths, which is where integrated optical-phased-array systems were operating in the past for lidar,” Corsetti says. “Here, we are meeting in the middle between standard photochemistry and silicon photonics by using visible-light-curable resins and visible-light-emitting chips to create this chip-based 3D printer. You have this merging of two technologies into a completely new idea.”

Their prototype consists of a single photonic chip containing an array of 160-nanometer-thick optical antennas. (A sheet of paper is about 100,000 nanometers thick.) The entire chip fits onto a U.S. quarter.

When powered by an off-chip laser, the antennas emit a steerable beam of visible light into the well of photocurable resin. The chip sits below a clear slide, like those used in microscopes, which contains a shallow indentation that holds the resin. The researchers use electrical signals to nonmechanically steer the light beam, causing the resin to solidify wherever the beam strikes it.

A collaborative approach

But effectively modulating visible-wavelength light, which involves modifying its amplitude and phase, is especially tricky. One common method requires heating the chip, but this is inefficient and takes a large amount of physical space.

Instead, the researchers used liquid crystal to fashion compact modulators they integrate onto the chip. The material’s unique optical properties enable the modulators to be extremely efficient and only about 20 microns in length.

A single waveguide on the chip holds the light from the off-chip laser. Running along the waveguide are tiny taps which tap off a little bit of light to each of the antennas.

The researchers actively tune the modulators using an electric field, which reorients the liquid crystal molecules in a certain direction. In this way, they can precisely control the amplitude and phase of light being routed to the antennas.

But forming and steering the beam is only half the battle. Interfacing with a novel photocurable resin was a completely different challenge.

The Page Group at UT Austin worked closely with the Notaros Group at MIT, carefully adjusting the chemical combinations and concentrations to zero-in on a formula that provided a long shelf-life and rapid curing.

In the end, the group used their prototype to 3D print arbitrary two-dimensional shapes within seconds.

Building off this prototype, they want to move toward developing a system like the one they originally conceptualized — a chip that emits a hologram of visible light in a resin well to enable volumetric 3D printing in only one step.

“To be able to do that, we need a completely new silicon-photonics chip design. We already laid out a lot of what that final system would look like in this paper. And, now, we are excited to continue working towards this ultimate demonstration,” Jelena Notaros says.

This work was funded, in part, by the U.S. National Science Foundation, the U.S. Defense Advanced Research Projects Agency, the Robert A. Welch Foundation, the MIT Rolf G. Locher Endowed Fellowship, and the MIT Frederick and Barbara Cronin Fellowship.

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at A*STAR’s Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

John Joannopoulos, an innovator and mentor in the fields of theoretical condensed matter physics and nanophotonics, has been named the recipient of the 2024-2025 James R. Killian Jr. Faculty Achievement Award.

Joannopoulos is the Francis Wright Davis Professor of Physics and director of MIT’s Institute for Soldier Nanotechnologies. He has been a member of the MIT faculty for 50 years.

“Professor Joannopoulos’s profound and lasting impact on the field of theoretical condensed matter physics finds its roots in his pioneering work in harnessing ab initio physics to elucidate the behavior of materials at the atomic level,” states the award citation, which was announced at today’s faculty meeting by Roger White, chair of the Killian Award Selection Committee and professor of philosophy at MIT. “His seminal research in the development of photonic crystals has revolutionized understanding of light-matter interactions, laying the groundwork for transformative advancements in diverse fields ranging from telecommunications to biomedical engineering.”

The award also honors Joannopoulos’ service as a “legendary mentor to generations of students, inspiring them to achieve excellence in science while at the same time facilitating the practical benefit to society through entrepreneurship.”

The Killian Award was established in 1971 to recognize outstanding professional contributions by MIT faculty members. It is the highest honor that the faculty can give to one of its members.

“I have to tell you, it was a complete and utter surprise,” Joannopoulos told MIT News shortly after he received word of the award. “I didn’t expect it at all, and was extremely flattered, honored, and moved by it, frankly.”

Joannopoulous has spent his entire professional career at MIT. He came to the Institute in 1974, directly after receiving his PhD in physics at the University of California at Berkeley, where he also earned his bachelor’s degree. Starting out as an assistant professor in MIT’s Department of Physics, he quickly set up a research program focused on theoretical condensed matter physics.

Over the first half of his MIT career, Joannopoulos worked to elucidate the fundamental nature of the electronic, vibrational, and optical structure of crystalline and amorphous bulk solids, their surfaces, interfaces, and defects. He and his students developed numerous theoretical methods to enable tractable and accurate calculations of these complex systems.

In the 1990s, his work with microscopic material systems expanded to a new class of materials, called photonic crystals — materials that could be engineered at the micro- and nanoscale to manipulate light in ways that impart surprising and exotic optical qualities to the material as a whole.

“I saw that you could create photonic crystals with defects that can affect the properties of photons, in much the same way that defects in a semiconductor affect the properties of electrons,” Joannopoulos says. “So I started working in this area to try and explore what anomalous light phenomena can we discover using this approach?”

Among his various breakthroughs in the field was the realization of a “perfect dielectric mirror” — a multilayered optical device that reflects light from all angles as normal metallic mirrors do, and that can also be tuned to reflect and trap light at specific frequencies. He and his colleagues saw potential for the mirror to be made into a hollow fiber that could serve as a highly effective optical conduit, for use in a wide range of applications. To further advance the technology, he and his colleagues launched a startup, which has since developed the technology into a flexible, fiber-optic “surgical scalpel.”

Throughout his career, Joannopoulos has helped to launch numerous startups and photonics-based technologies.

“His ability to bridge the gap between academia and industry has not only advanced scientific knowledge but also led to the creation of dozens of new companies, thousands of jobs, and groundbreaking products that continue to benefit society to this day,” the award citation states.

In 2006, Joannopoulos accepted the position as director of MIT’s Institute for Soldier Nanotechnologies (ISN), a collaboration between MIT researchers, industry partners, and military defense experts, who seek innovations to protect and enhance soldiers’ survivability in the field. In his role as ISN head, Joannopoulos has worked across MIT, making connections and supporting new projects with researchers specializing in fields far from his own.

“I get a chance to explore and learn fascinating new things,” says Joannopoulos, who is currently overseeing projects related to hyperspectral imaging, smart and responsive fabrics, and nanodrug delivery. “I love that aspect of really getting to understand what people in other fields are doing. And they’re doing great work across many, many different fields.”

Throughout his career at MIT, Joannopoulos has been especially inspired and motivated by his students, many of whom have gone on to found companies, lead top academic and research institutions, and make significant contributions to their respective fields, including one student who was awarded the Nobel Prize in Physics in 1998.

“One’s proudest moments are the successes of one’s students, and in that regard, I’ve been extremely lucky to have had truly exceptional students over the years,” Joannopolous says.

His many contributions to academia and industry have earned Joannopoulos numerous honors and awards, including his election to both the National Academy of Sciences and the American Academy of Arts and Sciences. He is also a fellow of both the American Physical Society and the American Association for the Advancement of Science.

“The Selection Committee is delighted to have this opportunity to honor Professor John Joannopoulos: a visionary scientist, a beloved mentor, a great believer in the goodness of people, and a leader whose contributions to MIT and the broader scientific community are immeasurable,” the award citation concludes.

Engineers at MIT, Nanyang Technological University, and several companies have developed a compact and inexpensive technology for detecting and measuring lead concentrations in water, potentially enabling a significant advance in tackling this persistent global health issue.

The World Health Organization estimates that 240 million people worldwide are exposed to drinking water that contains unsafe amounts of toxic lead, which can affect brain development in children, cause birth defects, and produce a variety of neurological, cardiac, and other damaging effects. In the United States alone, an estimated 10 million households still get drinking water delivered through lead pipes.

“It’s an unaddressed public health crisis that leads to over 1 million deaths annually,” says Jia Xu Brian Sia, an MIT postdoc and the senior author of the paper describing the new technology.

But testing for lead in water requires expensive, cumbersome equipment and typically requires days to get results. Or, it uses simple test strips that simply reveal a yes-or-no answer about the presence of lead but no information about its concentration. Current EPA regulations require drinking water to contain no more that 15 parts per billion of lead, a concentration so low it is difficult to detect.

The new system, which could be ready for commercial deployment within two or three years, could detect lead concentrations as low as 1 part per billion, with high accuracy, using a simple chip-based detector housed in a handheld device. The technology gives nearly instant quantitative measurements and requires just a droplet of water.

The findings are described in a paper appearing today in the journal Nature Communications, by Sia, MIT graduate student and lead author Luigi Ranno, Professor Juejun Hu, and 12 others at MIT and other institutions in academia and industry.

The team set out to find a simple detection method based on the use of photonic chips, which use light to perform measurements. The challenging part was finding a way to attach to the photonic chip surface certain ring-shaped molecules known as crown ethers, which can capture specific ions such as lead. After years of effort, they were able to achieve that attachment via a chemical process known as Fischer esterification. “That is one of the essential breakthroughs we have made in this technology,” Sia says.

In testing the new chip, the researchers showed that it can detect lead in water at concentrations as low as one part per billion. At much higher concentrations, which may be relevant for testing environmental contamination such as mine tailings, the accuracy is within 4 percent.

The device works in water with varying levels of acidity, ranging from pH values of 6 to 8, “which covers most environmental samples,” Sia says. They have tested the device with seawater as well as tap water, and verified the accuracy of the measurements.

In order to achieve such levels of accuracy, current testing requires a device called an inductive coupled plasma mass spectrometer. “These setups can be big and expensive,” Sia says. The sample processing can take days and requires experienced technical personnel.

While the new chip system they developed is “the core part of the innovation,” Ranno says, further work will be needed to develop this into an integrated, handheld device for practical use. “For making an actual product, you would need to package it into a usable form factor,” he explains. This would involve having a small chip-based laser coupled to the photonic chip. “It’s a matter of mechanical design, some optical design, some chemistry, and figuring out the supply chain,” he says. While that takes time, he says, the underlying concepts are straightforward.

The system can be adapted to detect other similar contaminants in water, including cadmium, copper, lithium, barium, cesium, and radium, Ranno says. The device could be used with simple cartridges that can be swapped out to detect different elements, each using slightly different crown ethers that can bind to a specific ion.

“There’s this problem that people don’t measure their water enough, especially in the developing countries,” Ranno says. “And that’s because they need to collect the water, prepare the sample, and bring it to these huge instruments that are extremely expensive.” Instead, “having this handheld device, something compact that even untrained personnel can just bring to the source for on-site monitoring, at low costs,” could make regular, ongoing widespread testing feasible.

Hu, who is the John F. Elliott Professor of Materials Science and Engineering, says, “I’m hoping this will be quickly implemented, so we can benefit human society. This is a good example of a technology coming from a lab innovation where it may actually make a very tangible impact on society, which is of course very fulfilling.”

“If this study can be extended to simultaneous detection of multiple metal elements, especially the presently concerning radioactive elements, its potential would be immense,” says Hou Wang, an associate professor of environmental science and engineering at Hunan University in China, who was not associated with this work.

Wang adds, “This research has engineered a sensor capable of instantaneously detecting lead concentration in water. This can be utilized in real-time to monitor the lead pollution concentration in wastewater discharged from industries such as battery manufacturing and lead smelting, facilitating the establishment of industrial wastewater monitoring systems. I think the innovative aspects and developmental potential of this research are quite commendable.”

Wang Qian, a principal research scientist at the Institute of Materials Research in Singapore, who also was not affiliated with this work, says, “The ability for the pervasive, portable, and quantitative detection of lead has proved to be challenging primarily due to cost concerns. This work demonstrates the potential to do so in a highly integrated form factor and is compatible with large-scale, low-cost manufacturing.”

The team included researchers at MIT, at Nanyang Technological University and Temasek Laboratories in Singapore, at the University of Southampton in the U.K., and at companies Fingate Technologies, in Singapore, and Vulcan Photonics, headquartered in Malaysia. The work used facilities at MIT.nano, the Harvard University Center for Nanoscale Systems, NTU’s Center for Micro- and Nano-Electronics, and the Nanyang Nanofabrication Center.

New technical papers added to Semiconductor Engineering’s library this week.

More Reading
Technical Paper Library home

The post Chip Industry Technical Paper Roundup: May 13 appeared first on Semiconductor Engineering.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

Experts at the Table: Semiconductor Engineering sat down to talk about what CMOS and photonics engineers need to know to successfully collaborate, with James Pond, fellow at Ansys; Gilles Lamant, distinguished engineer at Cadence; and Mitch Heins, business development manager for photonic solutions at Synopsys. What follows are excerpts of that conversation. To view part one of this discussion, click here. Part two is here.

L-R: Ansys’s Pond, Cadence’s Lamant, Synopsys’ Heins

SE: What do engineers who have spent their careers in CMOS need to know about designing for photonics?

Lamant:  It’s hard, no illusion. I had good mentors, including both James and Mitch, so I actually did that transition. Ten years ago, I knew nearly nothing about photonics. It takes having good mentors who can help you. That’s the biggest thing. It’s not enough to just try the software on your own. In addition, having an RF background is very useful in many ways. Photonics is the multiplication of RF. In photonics, you have multiple modes. In RF, you tend to only consider one mode, but a lot of the theory behind photonics is very much a generalization of RF.

Heins: We try to make our photonics flow look as much as we can like our electronics flow. We try to take the last 30 to 40 years of learning in EDA and apply it to photonics. One thing we see a lot is that when people are coming right out of school in photonics, they don’t necessarily have a deep background in how to do IC design. There are a lot of things we’ve learned, like design rule checking, that we now take for granted. It’s like breathing. You’ve got to do it. Layout versus schematic, you’ve got to do it. Even circuit-level simulation. As CMOS veterans, you’d think, of course, you always simulate your circuit before you go to manufacture, but that’s not the case in photonics.

Lamant: Those people actually know photonics, but they don’t know how to create a system. This is a different type of challenge. People who know photonics, know how to make a device. They’re expert at that. But they have no idea how to take that device and bring it to a full system that they can sell. I see that in so many startups. It’s not to make the point for EDA software. They use free software. They use Klayout and all those things that they have access to in the university. But all of those tools are not part of the ecosystem of trying to make a system. They say, ‘We wrote a custom simulator to simulate our ring.’ But the question then is, ‘How do you simulate the driver for your ring that goes with it?’ I see many startups fail because they don’t have that ability to take it from academic thinking to production.

You have the electronics people trying to do photonics, they have some methodology background, and other things, but they have a gap in knowledge. Fortunately, they can get caught up, especially if they’re an analog designer or an RF designer. They can close that gap by talking to the right people. Unfortunately, the people who know photonics do not have the knowledge of how to make a full system out of it, and this is greatly hurting the photonics world.

Pond: I would agree. We have two worlds of engineers who have been coming together over the last decade or so. Those who came from an EDA background — electrical circuit design, especially RF — have probably had the easiest time. We’ve been doing better and better for them. Ten years ago there was nothing. Now, there’s a more traditional workflow that looks more like an EDA workflow. Still, they have a lot to learn. But the workflow, the cockpit, and so on, follows along with the EDA model.

In the other direction, maybe we haven’t done quite as good a job because people coming from a photonics background can be really thrown off by the scale and complexity of EDA tools. My impression, coming from photonics, is EDA tools have been developed over many decades. When that happens, you end up with tools that are incredibly powerful, but you wonder if they’d been developed more recently, maybe things wouldn’t be done this way. There’s a resistance on the photonic engineer side to dive into that world because there’s a lot to learn about the EDA workflows. People from photonics have to embrace and take on that EDA world, because, as Gilles says, it’s necessary, it really has to be done.

Heins:  Now, you’re seeing a ton of work going into how to apply AI to help folks bring these kinds of more complex flows under control. There’s so much to learn, but if AI can help you take care of the plumbing, if you will, you can advance much faster. We already extensively use AI for SoCs or packaged designs where you have tens and hundreds of billions of transistors. Photonics is a different vector. The signal itself is much more complex than electrical. The optimization that you have to go through is much more complex. But AI can help get a handle on that, so as we go forward, you’ll start to see these kinds of complexities simplified for people.

SE: Is there something analogous to error correction/parity checks in the photonics world?

Lamant: That can’t be analogized to photonics, because that’s about knowing the original signal and comparing it to the others. Once you have reconstituted your data, and it’s back to being a digital set of bits, then you have a parity check or different types of things that today have nothing to do with photonics because it’s the physical link. In physical links, you can do retiming or a lot of things, but the error correction happens independently, on both sides.

Heins: Tuning might be something closer to it. If my resonance frequencies are not as expected, can I detect that and then adjust for it? That happens a lot. You could think of those kinds of things as error correction.

Pond: Most of the kind of error correction we’re talking about is just using all the standard methods, whether you have an optical link or a copper link. But there are some really interesting things. We had a workflow, developed between Ansys and Cadence a few years ago on a PAM-4 system, where we did a driver simulation and the photonic link together. You look into shifting the timing of signals to compensate for different effects. If you look at the eye at different locations, it may look completely distorted and wrong, because you’re pre-compensating for an effect that’s going to come later through the photonic portion of the link. That’s one of the reasons why it’s important to be able to do the full system simulation. You can’t just independently optimize the driver electronics and the photonics. They have to be done together, so you can perform the signal correction work.

Heins: You do things like equalization. Dispersion is another one. You get different wavelengths traveling at different speeds, and we compensate for that. At the physical level, there are some corrections that do take place, depending on the kind of system you’re trying to make. If you’re in coherent systems, where path links matter, phase matters, that’s more like trying to make the circuit correct by construction, so that you don’t encounter problems.

That raises another issue, which is manufacturing variances. There, you’re back to doing lots of sensitivity analysis through Monte Carlo-type simulations, parameterized simulations, etc., where you’re trying to get a feel for the sensitivity of your device, to a shift that could occur, either through the manufacturing process or just as this system sits in its ecosystem of whatever’s around it. It’s not quite error correction, per se, but certainly trying to design for that is something we care about.

SE: Any concluding thoughts?

Lamant: There is a lot of wondering and pondering right now, but it’s also exciting. We’ve reached the point where photonics is here to stay and will be part of more and more things. Looking forward, the interesting question is where it will become part of the actual data processing. Sensing is a terrific application for photonics, but I am not totally sold on the actual data processing. I’m not even using the word “computing” here, because processing and computing are very different things. Photonics is probably never going to be doing general computing. It may be doing specialized niche, like a Fourier transform-type of processing, and it needs to be part of a system.

Heins: It comes down to two things. What will really happen with quantum computing? And will quantum computing use photonics? A lot of people are looking at photonics for quantum computing because you can do a lot more of that work at room temperature than at 4 Kelvin or something like that — not all of it, but big chunks of it. If quantum computing actually becomes more than prototypes, and photonics is a big part of that, that could shift the answer. The other big issue in compute is we don’t have memory for photonics. If someone makes a breakthrough where suddenly states can be stored in some fashion, then all bets are off and everything changes again. But at this point, I don’t see anything promising.

One of the biggest challenges we have going forward for the whole ecosystem, in general, is lack of standards in this space, which makes interoperability between tools from our companies very difficult. The signal in photonics is very complex. It’s actually complex math, with real and imaginary parts. There are a lot of extra things that we have to take into account, and a lot of times we don’t even have common nomenclature or agreement on metrics and how to measure things. This is going to take time, but it’s being pushed by customers driving us to work together. For example, chiplets are great for photonics because a photonic IC is a chiplet. But all of a sudden, now you’re in a mixed domain, multi-physics type of environment, and there are some huge challenges to make that all work together. We have a pretty good handle on system functional verification, design-for-test, and all these things in the electronic IC world. In photonics, we’ve got a lot of work to do.

Pond: For me, it’s been exciting. I’ve been doing this for more than 20 years. In 2022, when I saw the first product with fibers actually coming out of the package, that was the dream from 20 years back. It took a lot of effort to get there. Things have been maturing very fast, especially in the last decade. That’s really promising from an EDA/EPDA-type of workflow perspective. The datacoms, as we’ve all said, are proven and not going to go away, given the investment from foundries, which is going to continue and even accelerate. It’s exciting times for all these other applications, from sensing to quantum and so on. There’s a lot of innovation possible. It’s not clear what’s going to be a winner yet and what’s not, but it’s a great time to be in photonics.

Read parts one and two of the discussion:
Photonics: The Former And Future Solution
Twenty-five years ago, photonics was supposed to be the future of high technology. Has that future finally arrived?
The Challenges Of Working With Photonics
From curvilinear designs to thermal vulnerabilities, what engineers need to know about the advantages and disadvantages of photonics

The post Design Considerations In Photonics appeared first on Semiconductor Engineering.

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

Mo Mirvakili PhD ’17 was in the middle of an experiment as a postdoc at MIT when the Covid-19 pandemic hit. Grappling with restricted access to laboratory facilities, he decided to transform his bathroom into a makeshift lab. Arranging a piece of plywood over the bathtub to support power sources and measurement devices, he conducted a study that was later published in Science Robotics, one of the top journals in the field.

The adversity made for a good story, but the truth is that it didn’t take a global pandemic to force Mirvakili to build the equipment he needed to run his experiments. Even when working in some of the most well-funded labs in the world, he needed to piece together tools to bring his experiments to life.

“My journey reflects a broader truth: With determination and resourcefulness, many of us can achieve remarkable things,” he says. “There are so many people who don't have access to labs yet have great ideas. We need to make it easier for them to bring their experiments to life.”

That’s the idea behind Seron Electronics, a company Mirvakili founded to democratize scientific experimentation. Seron develops scientific equipment that precisely sources and measures power, characterizes materials, and integrates data into a customizable software platform.

By making sophisticated experiments more accessible, Seron aims to spur a new wave of innovation across fields as diverse as microelectronics, clean energy, optics, and biomedicine.

“Our goal is to become one of the leaders in providing accurate and affordable solutions for researchers,” Mirvakili says. “This vision extends beyond academia to include companies, governments, nonprofits, and even high school students. With Seron’s devices, anyone can conduct high-quality experiments, regardless of their background or resources.”

Feeling the need for constant power

Mirvakili earned his bachelor's and master's degrees in electrical engineering, followed by a PhD in mechanical engineering under MIT Professor Ian Hunter, which involved developing a class of high-performance thermal artificial muscles, including nylon artificial muscles. During that time, Mirvakili needed to precisely control the amount of energy that flowed through his experimental setups, but he couldn't find anything online that would solve his problem.

“I had access to all sorts of high-end equipment in our lab and the department,” Mirvakili recalls. “It’s all the latest, state-of-the-art stuff. But I had to bundle all these outside tools together for my work.”

After completing his PhD, Mirvakili joined Institute Professor Bob Langer’s lab as a postdoc, where he worked directly with Langer on a totally different problem in biomedical engineering. In Langer's famously prolific lab, he saw researchers struggling to control temperatures at the microscale for a device that was encapsulating drugs.

Mirvakili realized the researchers were ultimately struggling with the same set of problems: the need to precisely control electric current, voltage, and power. Those are also problems Mirvakili has seen in his more recent research into energy storage and solar cells. After speaking with researchers at conferences from around the world to confirm the need was widespread, he started Seron Electronics.

Seron calls the first version of its products the SE Programmable Power Platforms. The platforms allow users to source and measure precisely defined quantities of electrical voltage, current, power, and charge through a desktop application with minimal signal interference, or noise.

The equipment can be used to study things like semiconductor devices, actuators, and energy storage devices, or to precisely charge batteries without damaging their performance.

The equipment can also be used to study material performance because it can measure how materials react to precise electrical stimulation at a high resolution, and for quality control because it can test chips and flag problems.

The use cases are varied, but Seron’s overarching goal is to enable more innovation faster.

“Because our system is so intuitive, you reduce the time to get results,” Mirvakili says. “You can set it up in less than five minutes. It’s plug-and-play. Researchers tell us it speeds things up a lot.”

New frontiers

In a recent paper Mirvakili coauthored with MIT research affiliate Ehsan Haghighat, Seron’s equipment provided constant power to a thermal artificial muscle that integrated machine learning to give it a sort of muscle memory. In another study Mirvakili was not involved in, a nonprofit research organization used Seron’s equipment to identify a new, sustainable sensor material they are in the process of commercializing.

Many uses of the machines have come as a surprise to Seron’s team, and they expect to see a new wave of applications when they release a cheaper, portable version of Seron’s machines this summer. That could include the development of new bedside monitors for patients that can detect diseases, or remote sensors for field work.

Mirvakili thinks part of the beauty of Seron’s devices is that people in the company don’t have to dream up the experiments themselves. Instead, they can focus on providing powerful scientific tools and let the research community decide on the best ways to use them.

“Because of the size and the cost of this new device, it will really open up the possibilities for researchers," Mirvakili says. “Anyone who has a good idea should be able to turn that idea into reality with our equipment and solutions. In my mind, the applications are really unimaginable and endless.”

Flat screen TVs that incorporate quantum dots are now commercially available, but it has been more difficult to create arrays of their elongated cousins, quantum rods, for commercial devices. Quantum rods can control both the polarization and color of light, to generate 3D images for virtual reality devices.

Using scaffolds made of folded DNA, MIT engineers have come up with a new way to precisely assemble arrays of quantum rods. By depositing quantum rods onto a DNA scaffold in a highly controlled way, the researchers can regulate their orientation, which is a key factor in determining the polarization of light emitted by the array. This makes it easier to add depth and dimensionality to a virtual scene.

“One of the challenges with quantum rods is: How do you align them all at the nanoscale so they’re all pointing in the same direction?” says Mark Bathe, an MIT professor of biological engineering and the senior author of the new study. “When they’re all pointing in the same direction on a 2D surface, then they all have the same properties of how they interact with light and control its polarization.”

MIT postdocs Chi Chen and Xin Luo are the lead authors of the paper, which appears today in Science Advances. Robert Macfarlane, an associate professor of materials science and engineering; Alexander Kaplan PhD ’23; and Moungi Bawendi, the Lester Wolfe Professor of Chemistry, are also authors of the study.

Nanoscale structures

Over the past 15 years, Bathe and others have led in the design and fabrication of nanoscale structures made of DNA, also known as DNA origami. DNA, a highly stable and programmable molecule, is an ideal building material for tiny structures that could be used for a variety of applications, including delivering drugs, acting as biosensors, or forming scaffolds for light-harvesting materials.

Bathe’s lab has developed computational methods that allow researchers to simply enter a target nanoscale shape they want to create, and the program will calculate the sequences of DNA that will self-assemble into the right shape. They also developed scalable fabrication methods that incorporate quantum dots into these DNA-based materials.

In a 2022 paper, Bathe and Chen showed that they could use DNA to scaffold quantum dots in precise positions using scalable biological fabrication. Building on that work, they teamed up with Macfarlane’s lab to tackle the challenge of arranging quantum rods into 2D arrays, which is more difficult because the rods need to be aligned in the same direction.

Existing approaches that create aligned arrays of quantum rods using mechanical rubbing with a fabric or an electric field to sweep the rods into one direction have had only limited success. This is because high-efficiency light-emission requires the rods to be kept at least 10 nanometers from each other, so that they won’t “quench,” or suppress, their neighbors’ light-emitting activity.

To achieve that, the researchers devised a way to attach quantum rods to diamond-shaped DNA origami structures, which can be built at the right size to maintain that distance. These DNA structures are then attached to a surface, where they fit together like puzzle pieces.

“The quantum rods sit on the origami in the same direction, so now you have patterned all these quantum rods through self-assembly on 2D surfaces, and you can do that over the micron scale needed for different applications like microLEDs,” Bathe says. “You can orient them in specific directions that are controllable and keep them well-separated because the origamis are packed and naturally fit together, as puzzle pieces would.”

Assembling the puzzle

As the first step in getting this approach to work, the researchers had to come up with a way to attach DNA strands to the quantum rods. To do that, Chen developed a process that involves emulsifying DNA into a mixture with the quantum rods, then rapidly dehydrating the mixture, which allows the DNA molecules to form a dense layer on the surface of the rods.

This process takes only a few minutes, much faster than any existing method for attaching DNA to nanoscale particles, which may be key to enabling commercial applications.

“The unique aspect of this method lies in its near-universal applicability to any water-loving ligand with affinity to the nanoparticle surface, allowing them to be instantly pushed onto the surface of the nanoscale particles. By harnessing this method, we achieved a significant reduction in manufacturing time from several days to just a few minutes,” Chen says.

These DNA strands then act like Velcro, helping the quantum rods stick to a DNA origami template, which forms a thin film that coats a silicate surface. This thin film of DNA is first formed via self-assembly by joining neighboring DNA templates together via overhanging strands of DNA along their edges.

The researchers now hope to create wafer-scale surfaces with etched patterns, which could allow them to scale their design to device-scale arrangements of quantum rods for numerous applications, beyond only microLEDs or augmented reality/virtual reality.

“The method that we describe in this paper is great because it provides good spatial and orientational control of how the quantum rods are positioned. The next steps are going to be making arrays that are more hierarchical, with programmed structure at many different length scales. The ability to control the sizes, shapes, and placement of these quantum rod arrays is a gateway to all sorts of different electronics applications,” Macfarlane says.

“DNA is particularly attractive as a manufacturing material because it can be biologically produced, which is both scalable and sustainable, in line with the emerging U.S. bioeconomy. Translating this work toward commercial devices by solving several remaining bottlenecks, including switching to environmentally safe quantum rods, is what we’re focused on next,” Bathe adds.

The research was funded by the Office of Naval Research, the National Science Foundation, the Army Research Office, the Department of Energy, and the National Institute of Environmental Health Sciences.

Flat screen TVs that incorporate quantum dots are now commercially available, but it has been more difficult to create arrays of their elongated cousins, quantum rods, for commercial devices. Quantum rods can control both the polarization and color of light, to generate 3D images for virtual reality devices.

Using scaffolds made of folded DNA, MIT engineers have come up with a new way to precisely assemble arrays of quantum rods. By depositing quantum rods onto a DNA scaffold in a highly controlled way, the researchers can regulate their orientation, which is a key factor in determining the polarization of light emitted by the array. This makes it easier to add depth and dimensionality to a virtual scene.

“One of the challenges with quantum rods is: How do you align them all at the nanoscale so they’re all pointing in the same direction?” says Mark Bathe, an MIT professor of biological engineering and the senior author of the new study. “When they’re all pointing in the same direction on a 2D surface, then they all have the same properties of how they interact with light and control its polarization.”

MIT postdocs Chi Chen and Xin Luo are the lead authors of the paper, which appears today in Science Advances. Robert Macfarlane, an associate professor of materials science and engineering; Alexander Kaplan PhD ’23; and Moungi Bawendi, the Lester Wolfe Professor of Chemistry, are also authors of the study.

Nanoscale structures

Over the past 15 years, Bathe and others have led in the design and fabrication of nanoscale structures made of DNA, also known as DNA origami. DNA, a highly stable and programmable molecule, is an ideal building material for tiny structures that could be used for a variety of applications, including delivering drugs, acting as biosensors, or forming scaffolds for light-harvesting materials.

Bathe’s lab has developed computational methods that allow researchers to simply enter a target nanoscale shape they want to create, and the program will calculate the sequences of DNA that will self-assemble into the right shape. They also developed scalable fabrication methods that incorporate quantum dots into these DNA-based materials.

In a 2022 paper, Bathe and Chen showed that they could use DNA to scaffold quantum dots in precise positions using scalable biological fabrication. Building on that work, they teamed up with Macfarlane’s lab to tackle the challenge of arranging quantum rods into 2D arrays, which is more difficult because the rods need to be aligned in the same direction.

Existing approaches that create aligned arrays of quantum rods using mechanical rubbing with a fabric or an electric field to sweep the rods into one direction have had only limited success. This is because high-efficiency light-emission requires the rods to be kept at least 10 nanometers from each other, so that they won’t “quench,” or suppress, their neighbors’ light-emitting activity.

To achieve that, the researchers devised a way to attach quantum rods to diamond-shaped DNA origami structures, which can be built at the right size to maintain that distance. These DNA structures are then attached to a surface, where they fit together like puzzle pieces.

“The quantum rods sit on the origami in the same direction, so now you have patterned all these quantum rods through self-assembly on 2D surfaces, and you can do that over the micron scale needed for different applications like microLEDs,” Bathe says. “You can orient them in specific directions that are controllable and keep them well-separated because the origamis are packed and naturally fit together, as puzzle pieces would.”

Assembling the puzzle

As the first step in getting this approach to work, the researchers had to come up with a way to attach DNA strands to the quantum rods. To do that, Chen developed a process that involves emulsifying DNA into a mixture with the quantum rods, then rapidly dehydrating the mixture, which allows the DNA molecules to form a dense layer on the surface of the rods.

This process takes only a few minutes, much faster than any existing method for attaching DNA to nanoscale particles, which may be key to enabling commercial applications.

“The unique aspect of this method lies in its near-universal applicability to any water-loving ligand with affinity to the nanoparticle surface, allowing them to be instantly pushed onto the surface of the nanoscale particles. By harnessing this method, we achieved a significant reduction in manufacturing time from several days to just a few minutes,” Chen says.

These DNA strands then act like Velcro, helping the quantum rods stick to a DNA origami template, which forms a thin film that coats a silicate surface. This thin film of DNA is first formed via self-assembly by joining neighboring DNA templates together via overhanging strands of DNA along their edges.

The researchers now hope to create wafer-scale surfaces with etched patterns, which could allow them to scale their design to device-scale arrangements of quantum rods for numerous applications, beyond only microLEDs or augmented reality/virtual reality.

“The method that we describe in this paper is great because it provides good spatial and orientational control of how the quantum rods are positioned. The next steps are going to be making arrays that are more hierarchical, with programmed structure at many different length scales. The ability to control the sizes, shapes, and placement of these quantum rod arrays is a gateway to all sorts of different electronics applications,” Macfarlane says.

“DNA is particularly attractive as a manufacturing material because it can be biologically produced, which is both scalable and sustainable, in line with the emerging U.S. bioeconomy. Translating this work toward commercial devices by solving several remaining bottlenecks, including switching to environmentally safe quantum rods, is what we’re focused on next,” Bathe adds.

The research was funded by the Office of Naval Research, the National Science Foundation, the Army Research Office, the Department of Energy, and the National Institute of Environmental Health Sciences.