Energy loss in degenerate quantum surfaces due to piezoelectric interaction at low lattice temperatures

The theory of energy loss rate of the non-equilibrium electrons in a degenerate quantum surface due to piezoelectric interaction has been developed under the condition of low temperature when the well-known approximations of the traditional theory are hardly valid. Compared to the traditional results for non-degenerate surface layers the theory here reveals a complex and altogether different dependence of the loss rate upon the carrier energy and the lattice temperature. The numerical results for GaAs and ZnO show how significantly does the degeneracy level or the true phonon distribution or the inelasticity of the interaction affect the loss characteristics at low temperatures. The possible applications of the theory have been discussed.