A phonon laser based on the optical tweezing technique invented by Nobel Prize recipient Arthur Ashkin was developed by researchers from Rochester Institute of Technology (RIT) and the University of Rochester. The researchers demonstrated a mesoscopic, frequency-tunable phonon laser based on the center-of-mass oscillation of a silica nanosphere levitated in an optical tweezer under vacuum. The phonon laser can be used on single electrons, liquid droplets, and even on small biological organisms. In a standard optical laser, the properties of the light output are controlled by the material from which the laser is made. In this phonon laser, the motion of the material particle is governed by the optical feedback. Researchers from RIT and the University of Rochester proposed and demonstrated a phonon laser using an optically levitated nanoparticle. Courtesy of A. Nick Vamivakas and Michael Osadciw/University of Rochester illustration. This phonon laser could provide a pathway for a coherent source of phonons on the mesoscale that could be applied to fundamental problems in quantum mechanics as well as precision metrology applications. “We are very excited to see what the uses of this device are going to be — especially for sensing and information processing, given that the optical laser has so many, and still evolving, applications," said professor Mishkat Bhattacharya, who is also interested in using the device to explore fundamental quantum physics. The research was published in Nature Photonics (https://doi.org/10.1038/s41566-019-0395-5).