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Impurity Entanglement Entropy and the Kondo Screening Cloud

Erik S. Sørensen·Ming-Shyang Chang·Nicolas Laflorencie·Ian Affleck
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Abstract

The screening of an impurity spin by conduction electrons is associated with the formation of a large Kondo screening cloud, of size xi_K. We study the quantum entanglement between a region of size r surrounding the impurity and the rest of the sample, (of total size R) using Density Matrix Renormalization Group and analytic methods. The corresponding "impurity entanglement entropy", S_{imp}, is shown to be a universal scaling function of r/xi_K and r/R. We calculate this universal function using Fermi liquid theory in the regime xi_K << r.

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Erik S. Sørensen, Ming-Shyang Chang, Nicolas Laflorencie, Ian Affleck. 2006-06-28. Impurity Entanglement Entropy and the Kondo Screening Cloud. https://doi.org/10.1088/1742-5468%2F2007%2F01%2Fl01001

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