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arXiv · 1309.0475

Non-Gaussian Spatial Correlations Dramatically Weaken Localization

Hossein Javan Mard·Eric C. Andrade·Eduardo Miranda·Vladimir Dobrosavljević
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Abstract

We perform variational studies of the interaction-localization problem to describe the interaction-induced renormalizations of the effective (screened) random potential seen by quasiparticles. Here we present results of careful finite-size scaling studies for the conductance of disordered Hubbard chains at half-filling and zero temperature. While our results indicate that quasiparticle wave functions remain exponentially localized even in the presence of moderate to strong repulsive interactions, we show that interactions produce a strong decrease of the characteristic conductance scale g* signaling the crossover to strong localization. This effect, which cannot be captured by a simple renormalization of the disorder strength, instead reflects a peculiar non-Gaussian form of the spatial correlations of the screened disordered potential, a hitherto neglected mechanism to dramatically reduce the impact of Anderson localization (interference) effects.

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Hossein Javan Mard, Eric C. Andrade, Eduardo Miranda, Vladimir Dobrosavljević. 2015-02-09. Non-Gaussian Spatial Correlations Dramatically Weaken Localization. https://doi.org/10.1103/physrevlett.114.056401

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