Sound amplification by stimulated emission of radiation of the laser. In a SASER device, a source (e.g., an electric field as a pump) produces sound waves (lattice vibrations, phonons) that travel through an active medium. In this active medium, a stimulated emission of phonons leads to amplification of the sound waves, resulting in a sound beam coming out of the device. The sound wave beams emitted from such devices are highly coherent. The first successful SASERs were developed in 2009. Instead of a feedback-built wave of electromagnetic radiation (i.e., a laser beam), a SASER delivers a sound wave. SASER may also be referred to as "phonon laser",
Sound amplification by stimulated emission of radiation of the resonator. The radiation then, propagates along an axis parallel to the plane defined by the two resonator walls. The static electric field acting on the liquid with gas bubbles results in the deformation of dielectrics and therefore leads to a change in the volumes of the particles. We note that, the electromagnetic waves in the medium propagate with a velocity much greater than the velocity of sound in the same medium. This results to the assumption that the effective pump wave acting on the bubbles does not depend on the spatial coordinates. The pressure of a wave pump