Photoreflectance of a GaAs/In 0.5 Ga 0.5 P (ordered) Single Quantum Well Grown by Atomic Layer Epitaxy

We have studied the photoreflectance spectrum at 300K from a GaAs/In 0.5 Ga 0.5 p (ordered) single quantum well fabricated by atomic layer epitaxy. Comparison of the energies of the observed intersubband and barrier transitions with an envelope function model calculation yields a valence band offset of 350 ± 20 meV.