Multielectron excitations in x-ray-absorption spectra ofa-Si:H

Abstract

In this paper a detailed analysis of a multielectron excitation observed 124 eV above the a-Si:H K edge is reported. The cross section of this excitation is about 1.7% of the main edge. The onset of the transition is smooth compared with the K edge, but reaches the sudden limit in only about 25 eV. The excitation shows the presence of a fine structure, on its high-energy side. The dominant channel in the multielectron excitation has been identified as a 1s2p→${\epsilon }_p^{\mathcal{’}}$3p’ transition. Calculations in the Z+1 approximation within the framework of a previously proposed exchange model have shown a close agreement with the experimental data in all the transition region between the onset and the sudden limit.