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Quantum Hall Ferromagnetism in Graphene

Kentaro Nomura·A. H. MacDonald
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Abstract

Graphene is a two-dimensional carbon material with a honeycomb lattice and Dirac-like low-energy excitations. When Zeeman and spin-orbit interactions are neglected its Landau levels are four-fold degenerate, explaining the $4 e^2/h$ separation between quantized Hall conductivity values seen in recent experiments. In this paper we derive a criterion for the occurrence of interaction-driven quantum Hall effects near intermediate integer values of $e^2/h$ due to charge gaps in broken symmetry states.

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Kentaro Nomura, A. H. MacDonald. 2008-05-12. Quantum Hall Ferromagnetism in Graphene. https://doi.org/10.1103/physrevlett.96.256602

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