Department of Applied Physics and Materials Science - Applied Physics

News & Events


A Pathway to Longer-Lasting Lithium Batteries


The energy density of batteries have been a major challenge for consumer electronics, electric vehicles, and renewable energy sources. Professor Julia R. Greer has made a discovery that could lead to lithium-ion batteries that are both safer and more powerful. Findings provide guidance for how lithium-ion batteries, one of the most common kinds of rechargeable batteries, can safely hold up to 50 percent more energy. "Every power-requiring application would benefit from batteries with lithium instead of graphite anodes because they can power so much more," says Greer. "Lithium is lightweight, it doesn't occupy much space, and it's tremendously energy dense." [Caltech story]

Tags: APhMS research highlights MCE Julia Greer

Superconducting Twisted Bilayer Graphene—Magic not Needed?


A new study shows that superconductivity in twisted bilayer graphene can exist away from the magic angle when coupled to a two-dimensional semiconductor. "Our observations were quite unexpected. It implies that we only scratched the surface of graphene twistronics. These are exciting times for the field," says Stevan Nadj-Perge, Assistant Professor of Applied Physics and Materials Science. [Caltech story]

Tags: APhMS research highlights Stevan Nadj-Perge

Optical Microcomb Device May Result in Improved Telecommunications, Sensors, Clocks


Modern telecommunications often makes use of multiple lasers of different colors to transmit data, but a new device the size of a cigarette pack can replace them. A team of researchers from Caltech, UC Santa Barbara, and the Swiss Federal Institute of Technology Lausanne (EPFL) have developed a new device that will lead to improved optical data transmission and could have applications ranging from communications to the miniaturization of time standards or to the search for exoplanets. Their device converts laser light of a single frequency into an evenly spaced set of many distinct frequencies (a comb of frequencies). The resulting optical frequency microcomb is built from a single piece of silicon, in much the same way as computer chips. And its many colors can replace many separate lasers for data transmission. "The new approach makes the process as easy as switching on a room light," says co-author Kerry Vahala, Ted and Ginger Jenkins Professor of Information Science and Technology and Applied Physics and executive officer for Applied Physics and Materials Science. [Caltech story]

Tags: APhMS research highlights Kerry Vahala

Chengzhe Zhou Receives 2020 Richard B. Chapman Memorial Award


Chengzhe Zhou, a graduate student in Physics supervised by Professor Sandra Troian, is a recipient of the 2020 Richard B. Chapman Memorial Award. His doctorate research focuses on the development of novel theoretical and computational tools for quantifying the nonlinear evolution and control of moving liquid boundaries driven by external fields. He hopes his findings offer new and useful analytic tools for investigating emergent small-scale dynamic phenomena in strongly driven nonlinear systems. The Richard B. Chapman Memorial Award is given to an EAS graduate student in hydrodynamics who has distinguished himself or herself in research.

Tags: honors Richard B. Chapman Memorial Award Sandra Troian Chengzhe Zhou

Michael Yao Receives 2020 Henry Ford II Scholar Award


Applied physics student Michael Yao, advised by Professor Mikhail Shapiro and Professor Andrei Faraon, is a recipient of the 2020 Henry Ford II Scholar Award. At the intersection between physics and medicine, Michael is interested in how physical and computational tools can be used to enhance the ability to image and treat diseases within the body. This summer, he will be working as a SURF fellow to explore the applications of ultrasound in improving both the safety and efficacy of immunotherapy and other cancer treatments. Encouraged by his mentors and coursework at Caltech, Michael will be pursuing a physician-scientist training program following graduation. The Henry Ford II Scholar Award is funded under an endowment provided by the Ford Motor Company Fund. The award is made annually to engineering students with the best academic record at the end of the third year of undergraduate study.

Tags: APhMS honors Henry Ford II Scholar Award Mikhail Shapiro Michael Yao

New Superconducting Film Resists a Magnet's Power to Thwart It


To Professor Joseph Falson, electrons are like exotic supercars and his lab wants to build the racetrack. In Falson's analogy, he likens that to driving the supercar down a cobblestone street that limits its speed. "Our job is not to make the supercar, it's just to make the highway," he says. The problem for those who seek to study superconductivity and eventually make practical use of it is that, so far, it has been realized only at ultracold temperatures no warmer than -70 degrees Celsius. "There is a very strong push to realize room-temperature superconductivity—it is one of the holy grails of science," Falson says, "because then you are going to employ these materials in motors or transmission lines, and the loss would be significantly less. It would revolutionize society." [Caltech story]

Tags: APhMS research highlights Joseph Falson

Tiny Optical Cavity Could Make Quantum Networks Possible


Professor Andrei Faraon and team have shown that atoms in optical cavities—tiny boxes for light—could be foundational to the creation of a quantum internet. They identified a rare-earth ytterbium ion in the center of a beam. The ytterbium ions are able to store information in their spin for 30 milliseconds. In this time, light could transmit information to travel across the continental United States. "It's a rare-earth ion that absorbs and emits photons in exactly the way we'd need to create a quantum network," says Faraon. "This could form the backbone technology for the quantum internet." [Caltech story]

Tags: APhMS EE research highlights Andrei Faraon Andrei Ruskuc Jake Rochman John Bartholomew Yan Qi Huan

New Chip-Based Laser Gyroscope Measures Earth's Rotation


Optical gyroscopes are used in applications such as aircraft navigation systems, while MEMS gyroscopes are found in devices like smart phones. Professor Kerry J. Vahala has developed an optical gyroscope that combines some of the best characteristics of each into one device. "For more than 20 years, researchers have speculated about placing optical gyroscopes onto a chip very much like the highly successful MEMS gyroscopes. But until recently, there have been very few compelling experiments," Vahala says. [Caltech story]

Tags: APhMS research highlights Kerry Vahala IST

Microstructures Self-Assemble into New Materials


A new process developed at Caltech makes it possible for the first time to manufacture large quantities of materials whose structure is designed at a nanometer scale—the size of DNA's double helix. Pioneered by Professor Julia R. Greer, "nanoarchitected materials" exhibit unusual, often surprising properties—for example, exceptionally lightweight ceramics that spring back to their original shape, like a sponge, after being compressed. Now, a team of engineers at Caltech and ETH Zurich have developed a material that is designed at the nanoscale but assembles itself—with no need for the precision laser assembly. "We couldn't 3-D print this much nanoarchitected material even in a month; instead we're able to grow it in a matter of hours," says Carlos M. Portela, Postdoctoral Scholar. "It is exciting to see our computationally designed optimal nanoscale architectures being realized experimentally in the lab," says Dennis M. Kochmann, Visiting Associate. [Caltech story]

Tags: APhMS research highlights GALCIT MCE Julia Greer Dennis Kochmann postdocs Carlos Portela

Goddard Receives UCLA Samueli Lifetime Contribution Award


Professor William Goddard has been honored with the 2020 UCLA Samueli Lifetime Contribution Award for his significant contributions to the fields of engineering, quantum mechanics, physical chemistry and chemical physics. Goddard obtained his bachelor’s in engineering with highest honors from UCLA in 1960, and frequently collaborates with UCLA faculty members. “Each of Goddard’s academic achievements represents a key advance in its respective field,” said Yu Huang, a professor of materials science and engineering at UCLA. “He has deservedly been recognized nationally and internationally for his highly accomplished academic career and, furthermore, has kept in close touch with UCLA colleagues and maintained fruitful collaborations with numerous UCLA faculty members.” [UCLA story]

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