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arXiv · 0808.1586

Glassy states in fermionic systems with strong disorder and interactions

David J. Schwab·Sudip Chakravarty
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Abstract

We study the competition between interactions and disorder in two dimensions. Whereas a noninteracting system is always Anderson localized by disorder in two dimensions, a pure system can develop a Mott gap for sufficiently strong interactions. Within a simple model, with short-ranged repulsive interactions, we show that, even in the limit of strong interaction, the Mott gap is completely washed out by disorder for an infinite system for dimensions $D\le 2$. The probability of a nonzero gap falls onto a universal curve, leading to a glassy state for which we provide a scaling function for the frequency dependent susceptibility.

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David J. Schwab, Sudip Chakravarty. 2009-02-03. Glassy states in fermionic systems with strong disorder and interactions. https://doi.org/10.1103/physrevb.79.125102

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