Interaction-enhanced integer quantum Hall effect in disordered systems

Jun-Hui Zheng; Tao Qin; Walter Hofstetter

doi:10.1103/physrevb.99.125138

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arXiv · 1805.10491

Interaction-enhanced integer quantum Hall effect in disordered systems

Jun-Hui Zheng·Tao Qin·Walter Hofstetter

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Abstract

We study transport properties and topological phase transition in two-dimensional interacting disordered systems. Within dynamical mean-field theory, we derive the Hall conductance, which is quantized and serves as a topological invariant for insulators, even when the energy gap is closed by localized states. In the spinful Harper-Hofstadter-Hatsugai model, in the trivial insulator regime, we find that the repulsive on-site interaction can assist weak disorder to induce the integer quantum Hall effect, while in the topologically non-trivial regime, it impedes Anderson localization. Generally, the interaction broadens the regime of the topological phase in the disordered system.

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BibTeX RIS

Jun-Hui Zheng, Tao Qin, Walter Hofstetter. 2018-07-16. Interaction-enhanced integer quantum Hall effect in disordered systems. https://doi.org/10.1103/physrevb.99.125138

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