Kondo effect in two-dimensional disordered electron systems

TL;DR

This paper studies how disorder affects the Kondo effect in 2D electron systems, revealing a broad distribution of Kondo temperatures and non-Fermi-liquid behavior at low temperatures.

Contribution

It provides new insights into the impact of disorder on the Kondo effect using quantum Monte Carlo simulations, highlighting the emergence of non-Fermi-liquid behavior.

Findings

Distribution of Kondo temperature widens with increased disorder

Large weight of zero Kondo temperature as disorder increases

Average susceptibility diverges weakly at low temperatures

Abstract

We investigate the Kondo effect in two-dimensional disordered electron systems using a finite-temperature quantum Monte Carlo method. Depending on the position of a magnetic impurity, the local moment is screened or unscreened by the spin of the conduction electron. On the basis of the results, we show that the distribution of the Kondo temperature becomes wide and the weight at $T_K=0$ becomes large as randomness increases. The average susceptibility shows a weak power-law or logarithmic divergence at low temperature, indicating a non-Fermi-liquid behavior.