Generalized Schrieffer-Wolff Transformation of 2 Kondo Impurity Problem

T. Tzen Ong; B. A. Jones

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Generalized Schrieffer-Wolff Transformation of 2 Kondo Impurity Problem

T. Tzen Ong·B. A. Jones

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Abstract

We have carried out a generalized Schrieffer-Wolff transformation of an Anderson two-impurity Hamiltonian to study the low-energy spin interactions of the system. The second-order expansion yields the standard Kondo Hamiltonian for two impurities with additional scattering terms. At fouth-order, we get the well-known RKKY interaction. In addition, we also find an antiferromagnetic superexchange coupling and a correlated Kondo coupling between the two impurities.

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T. Tzen Ong, B. A. Jones. 2006-02-09. Generalized Schrieffer-Wolff Transformation of 2 Kondo Impurity Problem. https://arxiv.org/abs/cond-mat/0602223

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