Two-Impurity Anderson-Kondo Model: first order Impurity-correlation

J. Simonin

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Two-Impurity Anderson-Kondo Model: first order Impurity-correlation

J. Simonin

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Abstract

We analyze the consequences of a first-order (in the effective Kondo coupling) inter-impurity correlation present in the Two-Impurity Anderson Hamiltonian. This correlation generates a pair of Kondo Doublet states which are responsible for the first (higher energy) Kondo stage of these systems. Applied to systems of quantum dots in a semiconductor heterolayer, these Doublets predict a mainly ferromagnetic dot-dot spin correlation which is different than the expected from the second-order RKKY interaction. In order to effectively screen both dots, a parallel alignment of the dot-spins is favored by the interaction.

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J. Simonin. 2005-10-21. Two-Impurity Anderson-Kondo Model: first order Impurity-correlation. https://arxiv.org/abs/cond-mat/0510580

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