ACOUSTIC-PHONON EMISSION BY HOT 2D ELECTRONS - THE ANGULAR-DISTRIBUTION OF THE EMITTED PHONON POWER

Calculations of energy relaxation rate P of quasi-two-dimensional Ferm i electron gases formed in GaAs heterostructures have been performed. Detailed analysis of the emitted phonon power angular distribution in both reciprocal space and the substrate has been made. The numerical c alculations have been performed for 2D electron gases in the (001) pla ne. The strong dependence of the angular distribution on temperature a nd the 2D electron gas (2DEG) thickness parameter has been analysed. T he angular dependence of the emitted phonon frequency spectrum has bee n considered. The importance of screening and the phonon focusing has been discussed. The domination of the transverse phonon contribution h as been shown.