Relaxation dynamics of nonequilibrium electron-phonon gases in a polar semiconductor

The thermalization of nonequilibrium electrons and phonons is investigated theoretically within the framework of a semiclassical description of the Boltzmann equation. The electrons are assumed to be excited in the intraband absorption in a polar semiconductor and subsequently undergo a Frohlich interaction to generate hot phonons. The coupled nonlinear Boltzmann equations for the electron-phonon system are directly solved numerically utilizing a discretization scheme. Consequently, a detailed analysis is given of the relaxation dynamics of the distribution functions and the decay of the hot electron and phonon temperatures. (C) 2000 American Institute of Physics. [S0021-8979(00)02411-7].