Theory of Electrons in Solids - Electronic properties of semiconductor heterostructures, including energy and spin relaxation, will be studied as functions of confinement of the electrons by the structural formation and as functions of electron interaction among themselves and with other excitations. Specific systems for the proposed study are lateral superlattices on vicinal plane quantum wells for both III-V and silicon/germanium composites and p-type quantum wells. The theory of optical properties in these systems will be investigated and used to predict and to understand observed optical phenomena. In particular, the time evolution of the optical spectra with specific polarizations will be studied on a picosecond scale. Study of the electronic interaction will also be extended to solids with narrow electronic bands. %%% Semiconductor heterostuctures are layered composite structures having at least one very small dimension. Such structures are being investigated intensively for application, particularly as optoelectronic devices. This project will examine issues central to such applications, including the effect of the minute size on energy and spin relaxation. The optical properties, both static and dynamic, of this class of artificially structured materials will be examined. These studies are aimed at understanding the intrinsic effect of the heterostructure design on the desired characteristics, including optical frequency range, bandwidth, and sensitivity of the ultamate device.
