‘Tiniest earthquakes’ could shrink and speed up future smartphones

Researchers from the University of Colorado Boulder, the University of Arizona, and Sandia National Laboratories have developed a novel surface acoustic wave (SAW) phonon laser that generates microscopic, high-frequency vibrations—described as “the tiniest earthquakes imaginable”—across the surface of a microchip. These surface acoustic waves, which currently serve as precision filters in smartphones, GPS, and radar systems, are essential for clearing background noise in data transmission. However, existing SAW technology is bulky, requiring multiple chips and operating around 4 gigahertz. The new phonon laser device integrates the generation of these waves onto a single chip, powered by a simple battery, and achieves higher frequencies, potentially scaling into the hundreds of gigahertz. The device mimics the mechanics of a diode laser, using a layered structure composed of silicon, lithium niobate (a piezoelectric material), and indium gallium arsenide to amplify acoustic waves efficiently. This compact design allows vibrations to strengthen with each