Auger transition from orbitally degenerate systems: Effects of screening and multielectron excitations

TL;DR

This paper investigates Auger spectra in orbitally degenerate systems, highlighting how screening and multielectron excitations influence spectral features, with results aligning well with experimental data and prompting reinterpretation of spectral features.

Contribution

It introduces a method to calculate Auger spectra in orbitally degenerate Hubbard-like models considering screening and multielectron effects, revealing qualitative differences from simpler models.

Findings

Spectra differ significantly from fully-filled models due to screening effects.

Application to real systems shows strong agreement with experimental spectra.

Reinterpretation of spectral features based on the new model.

Abstract

We calculate Auger spectra given by the two-hole Green's function from orbitally degenerate Hubbard-like models as a function of correlation strength and band filling. The resulting spectra are qualitatively different from those obtained from fully-filled singly degenerate models due to the presence of screening dynamics and multielectron excitations. Application to a real system shows remarkable agreement with experimental results leading to reinterpretation of spectral features.