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arXiv · 0910.5459

Energy gaps at neutrality point in bilayer graphene in a magnetic field

E. V. Gorbar·V. P. Gusynin·V. A. Miransky
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Abstract

Utilizing the Baym-Kadanoff formalism with the polarization function calculated in the random phase approximation, the dynamics of the $\nu=0$ quantum Hall state in bilayer graphene is analyzed. Two phases with nonzero energy gap, the ferromagnetic and layer asymmetric ones, are found. The phase diagram in the plane $(\tilde{\Delta}_0,B)$, where $\tilde{\Delta}_0$ is a top-bottom gates voltage imbalance, is described. It is shown that the energy gap scales linearly, $\Delta E\sim 14 B[T]K, with magnetic field.

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E. V. Gorbar, V. P. Gusynin, V. A. Miransky. 2009-10-28. Energy gaps at neutrality point in bilayer graphene in a magnetic field. https://doi.org/10.1134/s0021364010060111

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