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arXiv · 1008.2614

Anomalous criticality in the quantum Hall transition at $n=0$ Landau level of graphene with chiral-symmetric disorders

Tohru Kawarabayashi·Takahiro Morimoto·Yasuhiro Hatsugai·Hideo Aoki
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Abstract

We investigate numerically whether the chiral symmetry is the sole factor dominating the criticality of the quantum Hall transitions in disordered graphene. When the disorder respects the chiral symmetry, the plateau-to-plateau transition at the $n=0$ Landau level is shown to become anomalous (i.e., step-function-like). Surprisingly, however, the anomaly is robust against the inclusion of the uniform next-nearest neighbor hopping, which degrades the chiral symmetry of the lattice models. We have also shown that the ac (optical) Hall conductivity exhibits a robust plateau structure when the disorder respects the chiral symmetry.

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Tohru Kawarabayashi, Takahiro Morimoto, Yasuhiro Hatsugai, Hideo Aoki. 2010-08-16. Anomalous criticality in the quantum Hall transition at $n=0$ Landau level of graphene with chiral-symmetric disorders. https://doi.org/10.1103/physrevb.82.195426

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