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arXiv · cond-mat/0612369

Hofstadter butterflies of bilayer graphene

Norbert Nemec·Gianaurelio Cuniberti
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Abstract

We calculate the electronic spectrum of bilayer graphene in perpendicular magnetic fields nonperturbatively. To accommodate arbitrary displacements between the two layers, we apply a periodic gauge based on singular flux vortices of phase $2π$. The resulting Hofstadter-like butterfly plots show a reduced symmetry, depending on the relative position of the two layers against each other. The split of the zero-energy relativistic Landau level differs by one order of magnitude between Bernal and non-Bernal stacking.

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Norbert Nemec, Gianaurelio Cuniberti. 2007-05-08. Hofstadter butterflies of bilayer graphene. https://doi.org/10.1103/physrevb.75.201404

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