The PI intends to study and characterize various semiconductor structures such as superlattices, quantum wells and heterojunctions by the electromodulation techniques of photoreflectance and electroreflectance. The Ft. Monmouth ETDL facility has an excellent MBE growth capability and they are already preparing such structures particularly the GaA1As/GaAs system and GaAs doping superlattices (hipi structures). Although Ft. Monmouth has certain techniques such as photoluminescence, Raman scattering, TEM, etc. to study these semiconductor systems they do not have an electromodulation spectroscopy cability. Therefore, this would be an excellent and very timely match-up of resources, expertise and interests.