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",
A-235 anti-ballistic missile system A-235 and the A-135 missile defense system [6]. According to foreign media reports, on November 18, 2015, the first successful launch of the Nudol missile and the third launch in the missile test program of the complex took place. Presumably, the deployment site of the A-235 missile defense system will be the former base area of the A-135 missile defense system near Moscow. According to the plan, the complex will have the capabilities to intercept the warheads of ballistic missiles, as well as spacecraft [4]. In May 2016, system elements were tested as part of the exercises of the Military