News & Events


Quantum and non-linear forces yield peculiar thermal expansion in silicon


Most materials expand when heated. At temperatures below room temperature, silicon shows the opposite behavior, shrinking as it is heated. Even at room temperature the normal thermal expansion of silicon is rather small. A team led by Professor Brent Fultz wanted to know why, and found that the unusual property is the result of quantum effects coupled by the nonlinear forces between atoms in silicon. [Read the paper]

Tags: APhMS research highlights Brent Fultz Dennis Kim

No Motor, No Battery, No Problem


Chiara Daraio, Professor of Mechanical Engineering and Applied Physics, and colleagues have developed robots capable of self-propulsion without using any motors, servos, or power supply. Instead, these first-of-their-kind devices paddle through water as the material they are constructed from deforms with temperature changes. "Combining simple motions together, we were able to embed programming into the material to carry out a sequence of complex behaviors," says Caltech postdoctoral scholar Osama R. Bilal, who is co-first author of the PNAS paper is titled "Harnessing bistability for directional propulsion of soft, untethered robots." [Caltech story]

Tags: research highlights Chiara Daraio MCE APh postdocs Osama Bilal

Solving Pieces of the Genetic Puzzle


Postdoctoral scholar Nathan Belliveau working in the laboratory of Professor Rob Phillips has applied a method called Sort-Seq to mutate small pieces of noncoding regions in E. coli and determined which regions contain binding sites. Binding sites are the locations where specialized proteins that are involved in transcription—the first step in the process of gene expression—attach to DNA. "Humans have such a wide variety of cells—muscle cells, neurons, photoreceptors, blood cells, to name a few," says Professor Phillips. "They all have the same DNA, so how do they each turn out so differently? The answer lies in the fact that genes can be regulated—turned on or off, dialed up and dialed down—differently in different tissues. Until now, there have been no general principles to help us understand how this regulation was encoded." [Caltech story]

Tags: research highlights Rob Phillips APh postdocs Nathan Belliveau

Butterfly Wings Inspire Light-Manipulating Surface for Medical Implants



Professor Hyuck Choo along with postdoctoral researchers Radwanul Hasan Siddique, and graduate student Vinayak Narasimhan working in the Choo lab have developed a synthetic analogue for eye implants that makes them more effective and longer-lasting. The work was inspired by tiny nanostructures on transparent butterfly wings. The eye implant is shaped like a tiny drum, the width of a few strands of hair. When inserted into an eye, its surface flexes with increasing eye pressure, narrowing the depth of the cavity inside the drum. That depth can be measured by a handheld reader, giving a direct measurement of how much pressure the implant is under. [Caltech story]

Tags: EE research highlights MedE Hyuck Choo Radwanul Hasan Siddique Vinayak Narasimhan

Graduate Student Wins AAAS Mass Media Fellowship


Giuliana Viglione, a graduate student in Professor Andrew Thompson’s group and a member of the first E111 class has been selected to join the 2018 American Association for the Advancement of Science (AAAS) Mass Media Science & Engineering Fellows Program. The fellows are placed at media organizations nationwide and trained to sharpening their abilities to communicate complex scientific issues to the public. In her research, Giuliana uses robots to investigate small-scale motions in the ocean and what their effect on climate may be.  She will be spending the summer working at King5, an NBC affiliate in Seattle, where she will use her expertise to report on the effects of climate change in the Pacific Northwest.

Tags: honors research highlights ESE Andrew Thompson Giuliana Viglione

Glowing Contact Lens Could Prevent A Leading Cause of Blindness


Hundreds of millions of people suffer from diabetes worldwide, putting them at risk for a creeping blindness, or diabetic retinopathy. Existing treatments, though effective, are painful and invasive, involving lasers and injections into the eyeball. Graduate student, Colin Cook working in Professor Yu-Chong Tai’s laboratory has invented a contact lens that when worn during sleep interrupts the process that destroys cells of the retina. He hopes his contact lenses will offer a solution that patients will be more willing to try because the effort involved is minimal, as are the side effects. [Caltech story]

Tags: research highlights MedE Yu-Chong Tai Colin Cook

Engineered Metasurfaces Replace Adhesive Tape in Specialized Microscope


The latest advance in a new type of optics aimed at improving microscopy started with a game of tennis three years ago between Mooseok Jang a graduate of Professor Changhuei Yang's lab and Yu Horie working with Professor Andrei Faraon. "The hope is that our work will prompt further interest in this area of optics and make this type of microscopy and its advantages feasible for practical, everyday use—not just as a proof of concept," says Josh Brake, a graduate student in Yang's lab who continues to work on the project with Faraon and Yang. [Caltech story]

Tags: EE research highlights Changhuei Yang MedE alumni Andrei Faraon Mooseok Jang APh Yu Horie Josh Brake

New Process Allows 3-D Printing of Nanoscale Metal Structures


Professor Julia Greer and graduate student Andrey Vyatskikh have created complex nanoscale metal structures using 3-D printing. The process, once scaled up, could be used in a wide variety of applications and opens the door to the creation of a new class of materials with unusual properties that are based on their internal structure. [Caltech story]

Tags: research highlights MedE MCE Julia Greer MatSci Andrey Vyatskikh

Caltech and Disney Engineers Collaborate on Robotics


Caltech and Disney Research have entered into a joint research agreement to pioneer robotic control systems and further explore artificial intelligence technologies. Pietro Perona will work with Disney roboticist Martin Buehler to create navigation and perception software that could allow robotic characters to safely move through dense crowds and interact with people. Aaron Ames will work with Disney Research's Lanny Smoot to further explore robot autonomy and machine learning by creating objects that can self-navigate and perform stunts. Yisong Yue has been working with engineers from Disney Research on the use of machine learning to analyze the behavior of soccer players and to measure audience engagement. [Caltech story]

Tags: EE research highlights MCE CMS Pietro Perona Yisong Yue Aaron Ames

Building Blocks to Create Metamaterials


Chiara Daraio, Professor of Mechanical Engineering and Applied Physics, and colleagues have created a method to systematically design metamaterials using principles of quantum mechanics. "Before our work, there was no single, systematic way to design metamaterials that control mechanical waves for different applications," Professor Daraio says. "Instead, people often optimized a design to fulfill a specific purpose, or tried out new designs based on something they saw in nature, and then studied what properties would arise from repeated patterns." [Caltech story]

Tags: research highlights Chiara Daraio MCE APh