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Fine structure of the lowest Landau level in suspended trilayer graphene

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 نشر من قبل Uli Zeitler
 تاريخ النشر 2013
  مجال البحث فيزياء
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Magneto-transport experiments on ABC-stacked suspended trilayer graphene reveal a complete splitting of the twelve-fold degenerated lowest Landau level, and, in particular, the opening of an exchange-driven gap at the charge neutrality point. A quantitative analysis of distinctness of the quantum Hall plateaus as a function of field yields a hierarchy of the filling factors: u=6, 4, and 0 are the most pronounced, followed by u=3, and finally u=1, 2 and 5. Apart from the appearance of a u=4 state, which is probably caused by a layer asymmetry, this sequence is in agreement with Hunds rules for ABC-stacked trilayer graphene.



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