Anomalous exciton condensation in graphene bilayers.

  title={Anomalous exciton condensation in graphene bilayers.},
  author={Yafis Barlas and Ren{\'e} C{\^o}t{\'e} and Jules Lambert and Allan H. MacDonald},
  journal={Physical review letters},
  volume={104 9},
In ordinary semiconductor bilayers, exciton condensates appear at total Landau-level filling factor nu{T}=1. We predict that similar states will occur in Bernal stacked graphene bilayers at many nonzero integer filling factors. For nu{T}=-3, 1 we find that the superfluid density of the exciton condensate vanishes and that a finite-temperature fluctuation-induced first order isotropic-smectic phase transition occurs when the layer densities are not balanced. These anomalous properties of bilayer… Expand

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