Liquid Dielectric with Dispersed Particles as an Active Medium for an "Acoustic" Laser

Abstract

The theoretical scheme of an "acoustic" laser is suggested. A liquid dielectric wiith dispersed particles is considered as an active medium. Pumping is created by an oscillating electric field that deforms dispersed volumes or by a piezoelectric emitter of a piston type. Two types of resonators (rectangular and cylindrical) are considered for this laser. Phase bunching of initially incoherent emitters (dispersed particles) is realized by acoustic radiation forces. The generation conditions for this "acoustic" laser are evaluated. It is shown that two types of losses must be overcome in order for generation to begin. The first type results from the energy dissipation in the active medium and the second one is caused by radiation losses at the boundaries of the resonator. The possibility of the creation of an "acoustic" laser with an extraordinary active medium (liquid helium with free electrons) is discussed.