The Kondo Resonance in Electron Spectroscopy

TL;DR

This paper reviews electron spectroscopy studies of the Kondo resonance in cerium and vanadium compounds, highlighting its theoretical and experimental understanding within impurity models and dynamical mean-field theory.

Contribution

It provides a comprehensive overview of spectroscopic investigations of the Kondo resonance, including comparisons with theoretical models and insights into phase transitions.

Findings

Spectroscopy data aligns with impurity and DMFT calculations.

Angle-resolved photoemission explores k-dependence of the resonance.

Kondo volume collapse explains cerium phase transition.

Abstract

The Kondo resonance is the spectral manifestation of the Kondo properties of the impurity Anderson model, and also plays a central role in the dynamical mean-field theory (DMFT) for correlated electron lattice systems. This article presents an overview of electron spectroscopy studies of the resonance for the 4f electrons of cerium compounds, and for the 3d electrons of V_2O_3, including beginning efforts at using angle resolved photoemission to determine the k-dependence of the resonance. The overview includes the comparison and analysis of spectroscopy data with theoretical spectra as calculated for the impurity model and as obtained by DMFT, and the Kondo volume collapse calculation of the cerium alpha-gamma phase transition boundary, with its spectroscopic underpinnings.