Radiative Recombination from Photoexcited Hot Carriers in GaAs

We report the first observation of the radiative recombination from photoexcited hot carriers in GaAs. Our results show that the hot carriers have an effective temperature which implies a Maxwellian distribution. This temperature increases with the excitation intensity. An empirical relationship between this temperature and the power transferred from the hot carriers to the lattice is in quantitative agreement with the theoretical predictions for carrier scattering by polar optical modes.