Investigation of plasmon sidebands by synchrotron radiation tuning of electron escape depths

Abstract

Photoelectron spectra of Al and Si have been excited by monochromatized synchrotron radiation at different photon energies. The plasmon loss structures produced by the elastic electrons from the Si 2p and Al 2p core levels have been investigated for different kinetic energies at the elastic electrons. Variation of the plasmon loss intensities for electron kinetic energies of 30–330 eV explains earlier reported absence of plasmon structure in uv photoelectron spectroscopy. The results also indicate that a model of extrinsic bulk plasmon excitation developed by Mahan and modified to account for surface effects could explain the observed threshold behavior of bulk plasmon intensity at low electron kinetic energies.