Sound amplification by stimulated emission of radiation mechanism into the active medium is the existence of superlattice layers that reflect the phonons back and force them to bounce repeatedly to amplify sound. Therefore, to proceed to an understanding of a SASER design we need to imagine it in analogy with a laser device. In a laser, the active medium is placed between two mirror surfaces (reflectors)of a Fabry–Pérot interferometer. A spontaneously emitted photon inside this interferometer can force excited atoms to decay a photon of same frequency, same momentum, same polarization and same phase. Because the momentum (as a vector) of the photon is nearly parallel to
Mechanically stimulated gas emission Mechanically stimulated gas emission Mechanically Stimulated Gas Emission Mechanically stimulated gas emission (MSGE) is a complex phenomenon embracing various physical and chemical processes occurring on the surface and in the bulk of a solid under applied mechanical stress and resulting in emission of gases. MSGE is a part of a more general phenomenon of Mechanically Stimulated Neutral Emission (MSNE). The specific characteristics of MSGE as compared with MSNE is that the emitted neutral particles are limited to gas molecules. MSGE is opposite to Mechanically Stimulated Gas Absorption that usually occurs under fretting corrosion of metals, exposure to gases at high