Effects of stimulated optical phonon decay on hot carriers in GaAs

We have considered energy transfer from highly nonequilibrium electron gas to crystal lattice via emission of high-frequency longitudinal optical (LO) phonons and their subsequent transformations. At high intensity of electron excitation, the daughter LA phonons resulting from LO-phonon decay accumulate in considerable numbers and cause the LO-phonon decay to be a stimulated process. The stimulated decay effectively decimates the LO phonons and thus prevents their reabsorption by the electrons. These effects being incorporated in description of the electron-phonon kinetics, we have obtained considerable intensification of energy transfer from the electron subsystem. We also qualitatively discuss the effects of stimulation for alternative channels of LO-phonon decay.