Phonon laser could make smartphone components smaller

Researchers reported a single‑chip surface acoustic wave 'phonon laser' that produced vibrations near 1 GHz; the work led by Matt Eichenfield and collaborators was published in Nature on Jan. 14.

Engineers demonstrated a surface acoustic wave phonon laser built on a single chip and reported generating vibrations near 1 GHz. The device uses a layered semiconductor and piezoelectric stack to produce and reinforce surface waves in a way the team likens to a laser for mechanical waves. The study was led by Matt Eichenfield with coauthors including Alexander Wendt and collaborators from the University of Arizona and Sandia National Laboratories. The findings were published in Nature on Jan. 14. Key facts: - The device is roughly half a millimeter long and stacks silicon, a thin layer of lithium niobate, and an ultrathin sheet of indium gallium arsenide. - Electric current in the indium gallium arsenide drives surface acoustic waves (SAWs) in the lithium niobate, and reflectors create repeated passes that amplify the waves similar to a laser cavity. - The team generated SAWs at about 1 gigahertz and reports the design could be pushed to tens or hundreds of gigahertz. - Conventional SAW components typically operate up to around 4 gigahertz and are used today as precise radio‑frequency filters in many consumer devices. - The research was led by Matt Eichenfield, with lead author Alexander Wendt, and lists collaborators from the University of Arizona and Sandia National Laboratories; the paper appeared in Nature on Jan. 14. Summary: The experiment demonstrates a single‑chip phonon laser that generates and amplifies surface acoustic waves using a semiconductor–piezoelectric material stack. The researchers say this approach can reach higher frequencies than typical SAW devices and aim to consolidate multiple radio signal processing functions onto a single chip. Further engineering and development toward practical devices were not detailed by the team.