Kondo temperature of magnetic impurities at surfaces

TL;DR

This paper presents a simple model that accurately predicts the Kondo temperatures of magnetic impurities on metal surfaces, based on local hybridization effects, aligning well with experimental STS data.

Contribution

The authors introduce a minimal model linking Kondo temperature to d-level occupation and hybridization, explaining surface impurity behavior with high experimental agreement.

Findings

Model accurately predicts Kondo temperatures for various metal surfaces.

Kondo temperature depends on d-level occupation and hybridization.

Excellent agreement with scanning tunneling spectroscopy experiments.

Abstract

Based on the experimental observation, that only the close vicinity of a magnetic impurity at metal surfaces determines its Kondo behaviour, we introduce a simple model which explains the Kondo temperatures observed for cobalt adatoms at the (111) and (100) surfaces of Cu, Ag, and Au. Excellent agreement between the model and scanning tunneling spectroscopy (STS) experiments is demonstrated. The Kondo temperature is shown to depend on the occupation of the d-level determined by the hybridization between adatom and substrate with a minimum around single occupancy.