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arXiv · 1105.3301

Two-Site Kondo Effect in Atomic Chains

N. Néel·R. Berndt·J. Kröger·T. O. Wehling·A. I. Lichtenstein·M. I. Katsnelson
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Abstract

Linear CoCu_nCo clusters on Cu(111) are fabricated by means of atomic manipulation. They represent a two-site Kondo system with tunable interaction. Scanning tunneling spectroscopy reveals oscillations of the Kondo temperature T_K with the number n of Cu atoms for n>=3. Density functional calculations show that the Ruderman-Kittel-Kasuya-Yosida interaction mediated by the Cu chains causes the oscillations. Calculations find ferromagnetic and antiferromagnetic interaction for n=1 and 2, respectively. Both interactions lead to a decrease of T_K as experimentally observed.

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N. Néel, R. Berndt, J. Kröger, T. O. Wehling, A. I. Lichtenstein, M. I. Katsnelson. 2011-05-17. Two-Site Kondo Effect in Atomic Chains. https://doi.org/10.1103/physrevlett.107.106804

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