Source: CERN Courier
Researchers from the University of Nottingham in the UK and the Lashkarev Institute of Semiconductor Physics in Ukraine have made what may be a sonic laser, demonstrating sound amplification by stimulated emission of radiation, that is, a SASER.
Anthony Kent and his colleagues created the device out of stacks of thin layers of AlAs/GaAs that form a superlattice. The layering plays the role of an acoustic mirror, and an electrical input drives the production of phonons via a rather complicated process involving quantum wells. The operating frequency is in the terahertz range, with wavelengths of a few nanometres making this potentially attractive for many applications, including imaging.