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Metal-insulator transition in the Hubbard model: a simple description including the Kondo effect

V. Yu. Irkhin·A. V. Zarubin
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Abstract

The electron spectrum structure in the half-filled Hubbard model is considered in terms of the one-particle Green's functions within many-electron representation. A simple analytical generalization of the single-site Hubbard-III approximation is obtained, which takes into account the Fermi excitations (Kondo terms). The problem of the metal-insulator transition is investigated. The occurrence of a three-peak density-of-states structure including the "Kondo" peak at the Fermi level is discussed. A comparison with large-d calculations is performed.

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V. Yu. Irkhin, A. V. Zarubin. 2001-06-21. Metal-insulator transition in the Hubbard model: a simple description including the Kondo effect. https://doi.org/10.1140/epjb%2Fe2004-00153-6

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