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arXiv · 0707.1301

Static Screening and Delocalization Effects in the Hubbard-Anderson Model

P. Henseler·J. Kroha·B. Shapiro
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Abstract

We study the suppression of electron localization due to the screening of disorder in a Hubbard-Anderson model. We focus on the change of the electron localization length at the Fermi level within a static picture, where interactions are absorbed into the redefinition of the random on-site energies. Two different approximations are presented, either one yielding a nonmonotonic dependence of the localization length on the interaction strength, with a pronounced maximum at an intermediate interaction strength. In spite of its simplicity, our approach is in good agreement with recent numerical results.

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P. Henseler, J. Kroha, B. Shapiro. 2008-01-25. Static Screening and Delocalization Effects in the Hubbard-Anderson Model. https://doi.org/10.1103/physrevb.77.075101

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