Microscopic Devices That Control Vibrations Could Allow Smaller Mobile Devices

Chiara Daraio, Professor of Mechanical Engineering and Applied Physics, and colleagues have developed phononic devices that include parts that vibrate extremely fast, moving back and forth up to tens of millions of times per second. The devices were developed by creating silicon nitride drums that are just 90 nanometers thick. The drums are arranged into grids, with different grid patterns having different properties. Professor Daraio, along with former Caltech postdoctoral scholar Jinwoong Cha, have shown that arrays of these drums can act as tunable filters for signals of different frequencies and can act like one-way valves for high-frequency waves. [Caltech story]