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arXiv · 1111.5894

Topologically protected Landau levels in bilayer graphene in finite electric fields

Tohru Kawarabayashi·Yasuhiro Hatsugai·Hideo Aoki
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Abstract

The zero-energy Landau level of bilayer graphene is shown to be anomalously sharp (delta-function like) against bond disorder as long as the disorder is correlated over a few lattice constants.The robustness of the zero-mode anomaly can be attributed to the preserved chiral symmetry. Unexpectedly, even when we apply a finite potential difference (i.e., an electric field) between the top and the bottom layers, the valley-split $n=0$ Landau levels remain anomalously sharp although they are now shifted away from the zero energy, while the $n=1$ Landau levels exhibit the usual behavior.

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Tohru Kawarabayashi, Yasuhiro Hatsugai, Hideo Aoki. 2011-11-25. Topologically protected Landau levels in bilayer graphene in finite electric fields. https://doi.org/10.1103/physrevb.85.165410

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