Type-I and type-II transitions in electroluminescence spectra of GaAs/AlAs monolayer multiquantum-well structures

Abstract We have investigated the temperature dependence of type-I and type-II optical transitions in electroluminescence spectra from type-II (GaAs) n /(AlAs) m multiquantum-well structures embedded in InAlP confinement layers. The experimental results confirm a thermally assisted up-conversion of electrons from the AlAs conduction band X-point into the energetically higher lying quantized GaAs Γ-states. This process yields to a remarkable enhancement of the radiative type-I recombination in the type-II structures.