Quantum Hall ferromagnetism in graphene.
نویسندگان
چکیده
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 fourfold degenerate, explaining the 4e2/h separation between quantized Hall conductivity values seen in recent experiments. In this Letter we derive a criterion for the occurrence of interaction-driven quantum Hall effects near intermediate integer values of e2/h due to charge gaps in broken symmetry states.
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عنوان ژورنال:
- Physical review letters
دوره 96 25 شماره
صفحات -
تاریخ انتشار 2006