Photoluminescence from GaAs quantum wells under high electric fields

Abstract

The room-temperature photoluminescence spectra of n-modulation doped GaAs–AlGaAs multiple quantum wells have been studied at high parallel electric fields in order to obtain the distribution function of the two-dimensional electron system under high field conditions. The spectra show thermalized energy distributions with electron temperatures of ∼600 K in the range where current instabilities indicate negative differential conductivity. This temperature is well below the value expected for bulk GaAs, and can be understood on the basis of real-space transfer of hot electrons into AlGaAs.