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arXiv · 0909.1362

Theory of the Magnetic-Field-Induced Insulator in Neutral Graphene

J. Jung·A. H. MacDonald
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Abstract

Recent experiments have demonstrated that neutral graphene sheets have an insulating ground state in the presence of an external magnetic field. We report on a $π$-band tight-binding-model Hartree-Fock calculation which examines the competition between distinct candidate insulating ground states. We conclude that for graphene sheets on substrates the ground state is most likely a field-induced spin-density-wave, and that a charge density wave state is possible for suspended samples. Neither of these density-wave states support gapless edge excitations.

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J. Jung, A. H. MacDonald. 2009-09-08. Theory of the Magnetic-Field-Induced Insulator in Neutral Graphene. https://doi.org/10.1103/physrevb.80.235417

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