HOT-ELECTRON TRANSPORT AND COUPLED-MODE OPTIC PHONON IN A POLAR SEMICONDUCTOR

The effect of coupled-mode-LO phonons on the electronic transport in a polar semiconductor is studied within a model which takes the internal thermalization time of the LO phonon system and the relaxation time of the whole lattice as parameters. Our analysis shows that although the hot-electron energy-loss to LO phonons is drastically enhanced and the LO-phonon-induced linear mobility is markedly reduced by the formation of coupled modes at low temperatures, in a realistic polar semiconductor when all the scattering mechanisms included, the coupled-mode effect on the transport properties is almost buried.