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Kondo effect of Co adatoms on Ag monolayers on noble metal surfaces

M. A. Schneider·P. Wahl·L. Diekhöner·L. Vitali·G. Wittich·K. Kern
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Abstract

The Kondo temperature $T_K$ of single Co adatoms on monolayers of Ag on Cu and Au(111) is determined using Scanning Tunneling Spectroscopy. $T_K$ of Co on a single monolayer of Ag on either substrate is essentially the same as that of Co on a homogenous Ag(111) crystal. This gives strong evidence that the interaction of surface Kondo impurities with the substrate is very local in nature. By comparing $T_K$ found for Co on Cu, Ag, and Au (111)-surfaces we show that the energy scale of the many-electron Kondo state is insensitive to the properties of surface states and to the energetic position of the projected bulk band edges.

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M. A. Schneider, P. Wahl, L. Diekhöner, L. Vitali, G. Wittich, K. Kern. 2004-09-15. Kondo effect of Co adatoms on Ag monolayers on noble metal surfaces. https://doi.org/10.1143/jjap.44.5328

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