Lifshitz transition in Kondo alloys

TL;DR

This paper investigates the electronic states of Kondo alloys, identifying a Lifshitz transition at a specific impurity concentration that may explain non-Fermi liquid behaviors observed experimentally.

Contribution

It introduces a theoretical framework predicting a Lifshitz transition in Kondo alloys, linking Fermi surface topology changes to non-Fermi liquid phenomena.

Findings

Identification of two Fermi liquid regimes

Prediction of a Lifshitz transition at x = nc

Discontinuity in quasiparticle count in the Fermi surface

Abstract

We study the low energy states of Kondo alloys as function of the magnetic impurity concentration per site, x, and the conduction electron average site occupation, nc. Using two complementary approaches, the mean-field coherent potential approximation and the strong coupling limit, we identify and characterize two different Fermi liquid regimes. We propose that both regimes are separated by a Lifshitz transition at x = nc. Indeed, we predict a discontinuity of the number of quasiparticles which are enclosed in the Fermi surface. This feature could provide a scenario for the non-Fermi liquid properties that were recently observed in Kondo alloy systems around x = nc.