News & Events

02-25-21

Devices known as optical parametric oscillators are among the widely used nonlinear resonators in optics; they are "nonlinear" in that there is light flowing into the system and light leaking out, but not at the same wavelengths. Though these oscillators are useful in a variety of applications, including in quantum optics experiments, the physics that underpins how their output wavelength, or spectrum, behaves is not well understood. "When you add strong nonlinearity to resonators, you enter what we call a 'rich physics regime,'" says Alireza Marandi, Assistant Professor of Electrical Engineering and Applied Physics. "'Rich' in physics terms usually means complicated and hard to use, but we need nonlinearities to create useful functionalities such as switching for computing." To be able to make full use of nonlinear optical resonators, researchers want to be able to understand and model the physics that underpin how they work. Marandi and his colleagues recently uncovered a potential way to engineer those rich physics, while discovering phase transitions in the light that is generated by the resonators. [Caltech story]

Tags: APhMS EE research highlights KNI Alireza Marandi

02-22-21

Paul Rothemund, Research Professor of Bioengineering, Computing and Mathematical Sciences, and Computation and Neural Systems, has developed a technique that allows him to precisely place microscopic devices formed from folded DNA molecules in not only a specific location but also in a specific orientation. This method for precisely placing and orienting DNA-based molecular devices may make it possible to use these molecular devices to power new kinds of chips that integrate molecular biosensors with optics and electronics for applications such as DNA sequencing or measuring the concentrations of thousands of proteins at once. [Caltech story]

Tags: research highlights CMS Paul Rothemund KNI CNS

02-16-21

As astronauts walk across the moon, land spacecraft on its surface, drive lunar rovers around, or complete other astronaut tasks, they kick up the dust, and that is a problem because it can cause premature wear on mechanical parts, damage to seals, and may pose a health risk for the people breathing it in. "The sun is shining directly on these particles and giving them an electric charge," says third-year Caltech undergraduate student Luis Pabon. "This causes it to stick to the astronaut's suit or to any sensors or cameras that you put out on the moon." The Caltech team's invention, named Habitat Orientable & Modular Electrodynamic Shield (HOMES), tackles the problem of moon dust entering a potential lunar habitat and wreaking havoc within. [Caltech story]

Tags: research highlights GALCIT MCE Luis Pabon

02-16-21

Metals that Work Like Magic, a podcast from the Wall Street Journal, features Jamil Tahir-Kheli, research staff member working with Carver Mead, Gordon and Betty Moore Professor of Engineering and Applied Science, Emeritus. The podcast focuses on the history of superconductivity research over the past forty years and potential applications.

Tags: EE research highlights CMS Carver Mead CNS Jamil Tahir-Kheli

01-25-21

Researchers from Caltech and NTT Research are collaborating to develop a high-speed Coherent Ising Machine (CIM). A CIM is a network of optical parametric oscillators (OPOs) programmed to solve problems that have been mapped to an Ising model, which is a mathematical abstraction of magnetic systems composed of competitively interacting spins, or angular momentums of fundamental particles. The principal investigator at Caltech for this four-and-a-half-year joint project is Kerry Vahala, Ted and Ginger Jenkins Professor of Information Science and Technology and Applied Physics; Executive Officer for Applied Physics and Materials Science. “We are delighted at the prospect of working with Professor Vahala to develop an extremely small and high-speed CIM,” said NTT Research PHI Lab Director, Yoshihisa Yamamoto. “This work will advance our understanding of the CIM’s capabilities, map well with ongoing and related work with other institutions, provide new demonstrations of this awesomely powerful new information system and, we hope, set standards for the CIM’s speed and size.” [NTT Research story] [Business Wire story]

Tags: APhMS research highlights Kerry Vahala KNI

01-14-21

There are things in life that can be predicted reasonably well. The tides rise and fall. A billiard ball bounces around a table according to orderly geometry. And then there are things that defy easy prediction: The hurricane that changes direction without warning. The splashing of water in a fountain. These phenomena and others like them can be described as chaotic systems. Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering, has developed a new tool that might help to better understand chaotic systems. [Caltech story]

Tags: EE research highlights MedE KNI Lihong Wang

01-04-21

Julia Greer, Ruben F. and Donna Mettler Professor of Materials Science, Mechanics and Medical Engineering; Fletcher Jones Foundation Director of the Kavli Nanoscience Institute, has developed a process for generating three-dimensional architected polymers with heat-dependent "shape memory" properties: that is, when heated, the material folds and unfolds itself into a new preordained shape. These shape memory polymers could one day be used to perform complex tasks inside the human body, such as unclogging a blocked artery or pulling out a blood clot. [Caltech story]

Tags: APhMS research highlights MedE Julia Greer KNI Luizetta Elliott

12-07-20

Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering, has received funding for neuroscience projects from the National Institutes of Health's Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Wang and his team aim to develop a technology called 3D photoacoustic computed tomography (PACT) that will rapidly image large-scale neural activity in human brains with high sensitivity. "Photoacoustic imaging of adult human brains is one of the most challenging frontiers in our field," says Wang. "It requires innovation to overcome the signal attenuation and wavefront distortion due to the skull. I'm glad that the NIH has the vision to fund this worthy research direction." [Caltech story]

Tags: EE research highlights MedE KNI Lihong Wang

12-07-20

Crystals are usually good at conducting heat. By definition, their atomic structure is highly organized, which allows atomic vibrations—heat—to flow through them as a wave. Austin Minnich, Professor of Mechanical Engineering and Applied Physics, has discovered why a perfect crystal is not good at conducting heat, although it seemingly should be. "We have found that quantum mechanical effects can play a huge role in setting the thermal transport properties of materials even under familiar conditions like room temperature," says Austin Minnich. [Caltech story]

Tags: APhMS research highlights MCE KNI Austin Minnich

11-30-20

While existing models to predict the spread of a disease already exist, few, if any, incorporate artificial intelligence (AI). Yaser Abu-Mostafa, Professor of Electrical Engineering and Computer Science, is using a new model for predicting COVID-19's impact using AI and it dramatically outperforms other models, so much so that it has attracted the interest of public health officials across the country. "AI is a powerful tool, so it only makes sense to apply it to one of the most urgent problems the world faces," says Yaser Abu-Mostafa. [Caltech story]

Tags: EE research highlights CMS Yaser Abu-Mostafa CNS