Kondo Effect and Surface-State Electrons

TL;DR

This study investigates the influence of surface-state electrons on the Kondo effect of cobalt atoms on Ag(111) surfaces, finding that surface electrons play a minor role compared to bulk electrons, using low-temperature scanning tunneling spectroscopy.

Contribution

The paper provides experimental evidence that surface-state electrons have a limited impact on the Kondo effect of cobalt on Ag(111), challenging previous assumptions about their significance.

Findings

Kondo signature remains unchanged near surface steps

Surface-state electrons have a minor role in the Kondo effect

Bulk electrons are more influential in the observed phenomena

Abstract

We have used low temperature scanning tunneling spectroscopy and atomic manipulation to study the role of surface-state electrons in the Kondo effect of an isolated cobalt atom adsorbed on Ag(111). We show that the observed Kondo signature remains unchanged in close proximity of a monoatomic step, where the local density of states of the surface-state electrons is strongly perturbed. This result indicates a minor role for surface-state electrons in the Kondo effect of cobalt, compared to bulk electrons. A possible explanation for our findings is presented.