Kondo screening cloud in a one dimensional wire: Numerical renormalization group study

TL;DR

This paper uses numerical renormalization group techniques to study the Kondo screening cloud in a one-dimensional wire, improving spatial resolution and analyzing the temperature dependence of Kondo correlations.

Contribution

It introduces an improved NRG approach to better resolve the Kondo cloud and provides detailed calculations of spin correlation functions in a 1D wire.

Findings

Enhanced spatial resolution of the Kondo cloud using NRG

Calculated temperature dependence of Kondo correlations

Confirmed the existence of the Kondo screening cloud

Abstract

We study the Kondo model --a magnetic impurity coupled to a one dimensional wire via exchange coupling-- by using Wilson's numerical renormalization group (NRG) technique. By applying an approach similar to which was used to compute the two impurity problem we managed to improve the bad spatial resolution of the numerical renormalization group method. In this way we have calculated the impurity spin - conduction electron spin correlation function which is a measure of the Kondo compensation cloud whose existence has been a long standing problem in solid state physics. We also present results on the temperature dependence of the Kondo correlations.