Influence of electron-hole scattering on the plasma thermalization in doped GaAs

Abstract

The cooling of an electron-hole plasma in bulk n- and p-type doped GaAs is calculated without assuming complete thermalization between electrons and holes. Electron-hole scattering and nonequilibrium optical phonons are included in the simulation. In n-doped GaAs, we show that at low excitation density (i.e., when the photogenerated plasma density is small compared to the donor density), the electrons are at first colder than the holes but heat up quickly and subsequently stay close to the hole temperature. At low density in p-doped GaAs, however, the holes stay cold and the electron cooling is mainly controlled by electron-hole scattering.