Spontaneous parity breaking of graphene in the quantum Hall regime

Jean-Noël Fuchs

Laboratoire de Physique des Solides, Université Paris-Sud, Orsay, France

We propose that inversion symmetry of the graphene honeycomb lattice is spontaneously broken via a magnetic field dependent Peierls distortion. This out-of plane lattice distortion leads to valley splitting of the n=0 Landau level but not of the other Landau levels. Compared to quantum Hall valley ferromagnetism and to other mechanisms recently discussed in the literature, lattice distortion provides an alternative explanation to all the recently observed quantum Hall plateaus in graphene [Y. Zhang et al., Phys. Rev. Lett. 96, 136806 (2006)].