Kondo decoherence: finding the right spin model for iron impurities in gold and silver.
We exploit the decoherence of electrons due to magnetic impurities, studied via weak localization, to resolve a long-standing question concerning the classic Kondo systems of Fe impurities in the noble metals gold and silver: which Kondo-type model yields a realistic description of the relevant multiple bands, spin, and orbital degrees of freedom? Previous studies suggest a fully screened spin S Kondo model, but the value of S remained ambiguous. We perform density functional theory calculations that suggest S=3/2. We also compare previous and new measurements of both the resistivity and decoherence rate in quasi-one-dimensional wires to numerical renormalization group predictions for S=1/2, 1, and 3/2, finding excellent agreement for S=3/2.
Costi
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Institut für Festkörperforschung, Forschungszentrum Jülich, 52425 Jülich, Germany.
Bergqvist
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Weichselbaum
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von Delft
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Micklitz
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Rosch
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Mavropoulos
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Dederichs
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Mallet
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Saminadayar
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Bäuerle
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