ABSTRACT
Room temperature photoreflectance spectroscopy (RT PR) has been used to investigate (AlGa)As/GaAs MQW structures, grown by MBE. In addition to allowed and symmetry forbidden transitions between the confined states we observed transitions for energies higher than (AlGa)As barrier energy. These transitions were identified as transitions between unconfined electron states and unconfined heavy or light hole states. By using the envelope function model, the energies for above barrier transitions were determined and shown to agree with the experimental values obtained from photoreflectance spectra.
