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Excitonic gap, phase transition, and quantum Hall effect in graphene: strong-coupling regime

V. P. Gusynin·V. A. Miransky·S. G. Sharapov·I. A. Shovkovy
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Abstract

We suggest that physics underlying the recently observed removal of sublattice and spin degeneracies in graphene in a strong magnetic field describes a phase transition connected with the generation of excitonic and spin gaps. The strong-coupling regime is described using a phenomenological model with enhanced Zeeman splitting (spin gap) and excitonic gaps. The experimental form of the Hall conductivity $σ_{xy}$ with the additional $ν= 0, \pm 1$ plateaus is reproduced. The form of $σ_{xy}$ in the case of a strong-coupling regime with no enhanced Zeeman splitting is also discussed.

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V. P. Gusynin, V. A. Miransky, S. G. Sharapov, I. A. Shovkovy. 2006-12-19. Excitonic gap, phase transition, and quantum Hall effect in graphene: strong-coupling regime. https://arxiv.org/abs/cond-mat/0612488

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