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Delocalization due to correlations in two-dimensional disordered systems

Gabriel Vasseur·Dietmar Weinmann
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Abstract

We study the spectral statistics of interacting spinless fermions in a two-dimensional disordered lattice. Within a full quantum treatment for small few-particle-systems, we compute the low-energy many-body states numerically. While at weak disorder the interactions reduce spectral correlations and lead to localization, for the case of strong disorder we find that a moderate Coulomb interaction has a delocalizing effect. In addition, we observe a non-universal structure in the level-spacing distribution which we attribute to a mechanism reinforcing spectral correlations taking place in small systems at strong disorder.

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Gabriel Vasseur, Dietmar Weinmann. 2004-07-02. Delocalization due to correlations in two-dimensional disordered systems. https://doi.org/10.1140/epjb%2Fe2004-00380-9

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