Type-I and type-II transitions in electroluminescence spectra of GaAs/AlAs monolayer multiquantum-well structures
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 ?-states. This process yields to a remarkable enhancement of the radiative type-I recombination in the type-II structures.
electroluminescence monolayers optical transitions multiple quantum wells heterostructures