Electroluminescence from a GaAs/AlGaAs heterostructure at high electric fields: Evidence for real- & k-space transfer

We study impact-ionization-induced electroluminescence (EL) from a GaAs/AlGaAs heterostructure under high bias. In addition to k-space transfer (the Gunn effect), EL spectra indicate real-space (GaAs-to-AlGaAs) transfer. Microscopy shows strong EL near the anode.