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Impurity correlations in dilute Kondo alloys

Victor Barzykin·Ian Affleck
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Abstract

The single impurity Kondo model is often used to describe metals with dilute concentrations (n_i) of magnetic impurities. Here we examine how dilute the impurities must be for this to be valid by developing a virial expansion in impurity density. The O(n_i^2) term is determined from results on the 2-impurity Kondo problem by averaging over the RKKY coupling. The non-trivial fixed point of the 2-impurity problem could produce novel singularities in the heat capacity of dilute alloys at O(n_i^2).

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Victor Barzykin, Ian Affleck. 1999-09-13. Impurity correlations in dilute Kondo alloys. https://doi.org/10.1103/physrevb.61.6170

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