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arXiv · 1106.4418

The stability of the fractional quantum Hall effect in topological insulators

Ashley M. DaSilva
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Abstract

With the recent observation of graphene-like Landau levels at the surface of topological insulators, the possibility of fractional quantum Hall effect, which is a fundamental signature of strong correlations, has become of interest. Some experiments have reported intra-Landau level structure that is suggestive of fractional quantum Hall effect. This paper discusses the feasibility of fractional quantum Hall effect from a theoretical perspective, and argues that while this effect should occur, ideally, in the $n=0$ and $|n|=1$ Landau levels, it is ruled out in higher $|n|$ Landau levels. Unlike graphene, the fractional quantum Hall effect in topological insulators is predicted to show an interesting asymmetry between $n=1$ and $n=-1$ Landau levels due to spin-orbit coupling.

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Ashley M. DaSilva. 2011-06-22. The stability of the fractional quantum Hall effect in topological insulators. https://doi.org/10.1016/j.ssc.2011.07.001

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