Non-thermal photoexcited electron distributions in non-stoichiometric GaAs

Abstract

We present experimental evidence of inverted photoluminescence spectra in GaAs. The spectra are measured for As-rich GaAs layers with ultrashort (of the order of 30 - 60 fs) carrier lifetimes. Ensemble Monte Carlo simulations performed using the molecular dynamics approach confirm that the observed PL spectra are generated by non-thermalized carriers several tens of femtoseconds after their excitation.