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arXiv · 1107.0143

Fate of Dirac Points in a Vortex Superlattice

M. Kamfor·S. Dusuel·K. P. Schmidt·J. Vidal
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Abstract

We consider noninteracting fermions on the honeycomb lattice in the presence of a magnetic vortex superlattice. It is shown that depending on the superlattice periodicity, a gap may open at zero energy. We derive an expression of the gap in the small-flux limit but the main qualitative features are found to be valid for arbitrary fluxes. This study provides an original example of a metal-insulator transition induced by a strongly modulated magnetic field in graphene. At the same time our results directly apply to Kitaev's honeycomb model in a vortex superlattice.

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M. Kamfor, S. Dusuel, K. P. Schmidt, J. Vidal. 2011-07-01. Fate of Dirac Points in a Vortex Superlattice. https://doi.org/10.1103/physrevb.84.153404

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