Theory of dielectric screening and electron energy loss spectroscopy at surfaces
Abstract
We present an overview of theoretical techniques for describing electron energy loss processes in a reflection geometry. We start from a fundamental representation of the dielectric susceptibility tensor of the semi-infinite crystal, and illustrate how the screening becomes modified by the presence of the surface. A new formalism is also presented which improves upon existing techniques for modeling energy loss, is fully q-dependent, and accounts for nonlocality. The impact of nonlocality, local field effects and other many-body effects is discussed. The theory is supported by some explicit calculations on the GaAs(001)- c(4×4) surface. To cite this article: C. Hogan et al., C. R. Physique 10 (2009).
- Publication:
-
Comptes Rendus Physique
- Pub Date:
- July 2009
- DOI:
- 10.1016/j.crhy.2009.03.015
- Bibcode:
- 2009CRPhy..10..560H