Single-particle relaxation time of the two-dimensional electron gas in Si/SiGe: many-body effects
A. Gold
Centre d'Elaboration de Materiaux et d'Etudes Structurales (CEMES-CNRS), 31055 Toulouse, France
UFR-PCA, Université Paul Sabatier, 31062 Toulouse, France
Abstract
The single-particle relaxation time of the two-dimensional
electron gas in SiGe/Si/SiGe quantum wells is calculated. Many-body effects
beyond the random-phase approximation become important at low electron
density. For charged impurity scattering (remote doped) we analyze the
importance of these many-body effects as function of the electron density and
the spacer width. Induced by many-body effects a strong reduction of the
single-particle relaxation time at low electron density is predicted. We
describe the relation with the transport scattering time, we comment on
multiple-scattering effects and we discuss the determination of many-body
effects in existing samples.