Engineers Just Created a "phonon Laser" That Could Shrink Your Next Smartphone

Engineers have created a device that generates tiny earthquake-like vibrations on a microchip. The surface acoustic wave phonon laser produces ultra-fast surface waves that already play a role in smartphones and wireless technology. The single-chip design could deliver higher performance using less power than current systems. The research was led by Matt Eichenfield, an incoming faculty member at the University of Colorado Boulder. Scientists from the University of Arizona and Sandia National Laboratories also contributed. Their findings were published Jan. 14 in the journal Nature. Surface acoustic waves move along the surface of materials rather than through them. In smartphones they act as precise filters that separate useful radio signals from interference. The new phonon laser generates these waves in a way similar to how a conventional laser produces light. The device uses layers of silicon, lithium niobate and indium gallium arsenide. It is shaped like a bar about half a millimeter long. Researchers generated waves vibrating at about 1 gigahertz and said the design could reach tens or even hundreds of gigahertz. Existing surface acoustic wave systems often require two chips and an external power source. The new approach combines the functions on one chip that could run on a battery. Eichenfield said this phonon laser was the last domino standing that we needed to knock down. Now every component needed for a radio can be made on one chip using the same kind of technology, he said.