The principal investigator's previous theoretical work concentrated on the nonlinear optical and electro-optical properties of the asymmetric quantum wells and superlattices. He has shown that in such structures large optical nonlinearities can occur. He has also shown that these nonlinearities can be enhanced by Coulomb effects. Some of the theoretical results were confirmed experimentally by other scientists. He proposes to continue the theoretical research of novel quantum size heterostructures. The proposal involves the study of three new phenomena: a) carrier transport in the p-i-p-n and n-i-n-p modulation-doped superlattices; b)electroabsorption based on the Quantum Confined Stark effect in type II wide-bandgap superlattices; and, c) intersubband transitions in the asymmetric quantum wells in the magnetic field. This research will ascertain the potential for the new heterostructure-based transistors, photodetectors, and electro-optic modulators and switches. //
