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arXiv · 0911.0959

The Two-impurity Anderson Model Revisited: Competition between Kondo Effect and Reservoir-mediated Superexchange in Double Quantum Dots

Minchul Lee·Mahn-Soo Choi·Rosa Lopez·Ramon Aguado·Jan Martinek·Rok Zitko
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Abstract

We study a series-coupled double quantum dot in the Kondo regime modeled by the two-impurity Anderson model and find a new conduction-band mediated superexchange interaction that competes with Kondo physics in the strong Coulomb interaction limit. Our numerical renormalization group results, complemented with the higher-order Rayleigh-Schrödinger perturbation theory, show that the novel exchange mechanism leads to clear experimental consequences that can be checked in transport measurements through double quantum dots.

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Minchul Lee, Mahn-Soo Choi, Rosa Lopez, Ramon Aguado, Jan Martinek, Rok Zitko. 2009-11-05. The Two-impurity Anderson Model Revisited: Competition between Kondo Effect and Reservoir-mediated Superexchange in Double Quantum Dots. https://doi.org/10.1103/physrevb.81.121311

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