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Possible Broken Inversion and Time-Reversal Symmetry State of Electrons in Bilayer Graphene

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 نشر من قبل Xin-Zhong Yan
 تاريخ النشر 2012
  مجال البحث فيزياء
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With the two-band continuum model, we study the broken inversion and time-reversal symmetry state of electrons with finite-range repulsive interactions in bilayer graphene. With the analytical solution to the mean-field Hamiltonian, we obtain the electronic spectra. The ground state is gapped. In the presence of the magnetic field $B$, the energy gap grows with increasing $B$, in excellently agreement with the experimental observation. Such an energy gap behavior originates from the disappearance of a Landau level of $n$ = 0 and 1 states. The present result resolves explicitly the puzzle of the gap dependence of $B$.



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