AVS 46th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS3+EM-WeM

Invited Paper SS3+EM-WeM3
Electron Excitations and Optical Properties of Semiconductor Surfaces

Wednesday, October 27, 1999, 9:00 am, Room 604

Session: Surface Electronic Structure
Presenter: S.G. Louie, University of California, Berkeley and Lawrence Berkeley National Laboratory
Correspondent: Click to Email
The presence of electronic surface states and resonances often strongly modifies the structural, chemical, electronic, and optical properties of a surface. Over the past two decades, many sophisticated experimental methods (e.g., photoemission, scanning probes, and optical techniques) have been developed to investigate the spectroscopic properties of surfaces. In this talk, we discuss some of the theoretical developments in studying surface spectroscopic properties. Ab initio quasiparticle calculations can now be used to understand and predict surface-state excitation spectra such as those measured in photoemission and scanning tunneling spectroscopy experiments. A recent advance in treating excitonic effects further allows the first-principles study of surface optical processes. Results on several semiconductor surfaces will be presented. The possibility of using NMR chemical shifts as a probe of surface states will also be discussed.