Sound amplification by stimulated emission of radiation the lattice levels, until they escape from the lattice structure in a form of an ultrahigh frequency-phonon beam. Namely, a concerted emission of phonons can lead to coherent sound and an example of concerted phonon emission is the emission coming from quantum wells. This stands in similar paths with the laser where a coherent light can build up by the concerted stimulated emission of light from a lot of atoms. A SASER device transforms the electric potential energy in a single vibrational mode of the lattice (phonon). The medium where the amplification takes place, consists of stacks of thin layers
Sound amplification by stimulated emission of radiation means that, since bosons with the same energy can occupy the same place in space, phonons and photons are force carrier particles and they have integer spins. There are more allowed states available for occupancy in a phonon field than in a photon field. Therefore, since the density of terminal states in the phonon field exceeds that in a photon field (by up to ~10), phonon emission is by far the more likely event. We could also imagine a concept where the excitation of an electron briefly leads to vibration of the lattice and thus to phonon generation. The vibration