Static and dynamical properties of a magnetic impurity in a strongly correlated electronic system

TL;DR

This study investigates how a magnetic impurity interacts with a strongly correlated one-dimensional electronic system, revealing changes in spin and charge correlations and the influence of interactions on Kondo physics.

Contribution

It provides new insights into the static and dynamical properties of magnetic impurities in Hubbard models with strong correlations using numerical methods.

Findings

Static spin correlations show 2k_F periodicity.

Charge correlations exhibit 4k_F Friedel oscillations at large U.

On-site susceptibility decreases with increasing U, indicating higher Kondo temperature.

Abstract

Using numerical techniques we study the zero temperature properties of a substitutional magnetic impurity in a one-dimensional correlated system described by the Hubbard model with repulsive interaction $U$. We find that, while the static spin correlation maintains a $2k_F$ periodicity, the charge correlations show Friedel oscillations with a $4k_F$ periodicity for large values of $U$. The static on-site susceptibility decreases as the interactions in the chain are turned on and we interpret this as an increase of the Kondo temperature. For large values of $U$ the short range antiferromagnetic correlations dominate over the collective Kondo singlet formation.