Sound amplification by stimulated emission of radiation of a coherent amplification of THz sound. The THz stimulated phonon induced transitions between the electron superlattice states lead to this coherent amplification while processing a population inversion. An essential step towards coherent generation ("sasing") of THz sound and other active hypersound devices has been provided by this achievement of THz sound amplification. Generally, in a device where the threshold for "sasing" is achieved, the technique described by this proposed scheme could be used to measure the coherence time of the emitted hypersound. Sound amplification by stimulated emission of radiation Sound amplification by stimulated emission of radiation (SASER) refers to
A-235 anti-ballistic missile system eliminates the use within the limited armed conflict and other situations of this kind; secondly, the system must be mobile, without a rigid binding to any object or center; thirdly, it must provide interception at an altitude of at least 500–750 km, that is, at Low Earth Orbit] . A-235 anti-ballistic missile system A-235 PL-19 "Nudol" () is a Russian anti-ballistic missile and anti-satellite weapon system in development. This system is designed to deflect a nuclear attack on Moscow and important industrial regions. The main developer of the system is JSC Concern VKO Almaz-Antey. The new system should replace the