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arXiv · 0804.4762

Topological low-energy modes in N=0 Landau levels of graphene: a possibility of a quantum-liquid ground state

Yasuhiro Hatsugai·Takahiro Fukui·Hideo Aoki
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Abstract

We point out that the zero-energy Landau level of Dirac fermions in graphene can be, in the presence of a repulsive electron-electron interaction, split into two (levels) associated with a "bond ordering" formation having a "Kekule pattern", which respects the chiral symmetry. Since the Kekule pattern has a three-fold degeneracy, domain structures are implied, for which we show that in-gap states localized along the domain boundaries exist as topological states. Based on this a possibility of a quantum-liquid ground state of graphene in magnetic fields is discussed.

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Yasuhiro Hatsugai, Takahiro Fukui, Hideo Aoki. 2008-04-30. Topological low-energy modes in N=0 Landau levels of graphene: a possibility of a quantum-liquid ground state. https://doi.org/10.1016/j.physe.2007.09.164

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