Theoretical Solid State Physics

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

0087088 Cohen This grant supports a long-range, broad-based research program in condensed matter physics and materials science. The research covers the fields of semiconductors, metals, surfaces and interfaces, defects, superconductivity, materials under pressure, clusters, fullerene-based materials, nanotubes, conjugated polymers, and many-electron effects in solids. The major objective is to use quantum theory to explain and predict the properties of materials. Emphasis is placed on using realistic models, close collaborations with experimentalists, investigations and suggestions for producing novel and useful materials, development of new theoretical approaches, and predictions related to electronic and structural properties of solids. Many new techniques based on quantum theory were developed in this research program to enable accurate calculations for real materials. In particular, the ab initio pseudopotential method and total energy techniques are applied within the density functional formalism to compute ground-state properties. Excited-state (spectroscopic) phenomena are investigated using a first-principles self-energy approach based on the GW approximation for quasiparticle excitations and an ab initio two-particle Green's function method based on the Bethe-Saltpeter equation for optical excitations. Other studies rely on variational and diffusion Monte Carlo approaches, molecular dynamics simulations, dielectric function methods, BCS theory, density functional perturbation theory, and extensions of standard many-body theory. Proposed projects include understanding and predicting properties of nanotubes and nanocrystals; hard materials and mechanical properties; semiconductors, heterojunctions, and materials under pressure; NMR chemical shifts in solids and liquids; electron-hole interaction and optical properties of solids, defects, and polymers; quasiparticle excitations, lifetimes, and electron correlations in solids; and quantum computing and ransom access devices for computers. The research program has a strong history of supporting graduate students and postdoctoral associates. Because of this extensive involvement of graduate students and postdoctoral associates in these projects, expertise and knowledge are transferred nationally and internationally. %%% This grant supports a long-range, broad-based research program in condensed matter physics and materials science. The research covers the fields of semiconductors, metals, surfaces and interfaces, defects, superconductivity, materials under pressure, clusters, fullerene-based materials, nanotubes, conjugated polymers, and many-electron effects in solids. The major objective is to use quantum theory to explain and predict the properties of materials. Emphasis is placed on using realistic models, close collaborations with experimentalists, investigations and suggestions for producing novel and useful materials, development of new theoretical approaches, and predictions related to electronic and structural properties of solids. The research program has a strong history of supporting graduate students and postdoctoral associates. Because of this extensive involvement of graduate students and postdoctoral associates in these projects, expertise and knowledge are transferred nationally and internationally. ***