Kondo Effect in a Metal with Correlated Conduction Electrons: Diagrammatic Approach

TL;DR

This paper develops a diagrammatic 1/N expansion method to analyze the Kondo effect in metals with correlated conduction electrons, focusing on low-temperature properties and the influence of electron interactions.

Contribution

It introduces a novel diagrammatic approach within the 1/N expansion to study conduction electron correlations' effects on the Kondo impurity.

Findings

Characterizes the energy scale in weak conduction electron interactions

Calculates impurity valence, charge and magnetic susceptibilities, specific heat

Provides insights into ground state and low-energy excitations

Abstract

We study the low-temperature behavior of a magnetic impurity which is weakly coupled to correlated conduction electrons. To account for conduction electron interactions a diagrammatic approach in the frame of the 1/N expansion is developed. The method allows us to study various consequences of the conduction electron correlations for the ground state and the low-energy excitations. We analyse the characteristic energy scale in the limit of weak conduction electron interactions. Results are reported for static properties (impurity valence, charge susceptibility, magnetic susceptibility, and specific heat) in the low-temperature limit.