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Two-impurity Kondo problem for correlated electrons

Karen Hallberg·Reinhold Egger
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Abstract

The behavior of two magnetic impurities coupled to correlated electrons in one dimension is studied using the DMRG technique for several fillings. On-site Coulomb interactions among the electrons lead to a small Kondo screening cloud and an overall suppression of magnetic order. For arbitrary electronic correlations and large inter-impurity distances R, we find a 1/R^2 decay of magnetic correlations.

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Karen Hallberg, Reinhold Egger. 1997-02-18. Two-impurity Kondo problem for correlated electrons. https://doi.org/10.1103/physrevb.55.r8646

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