Spin Versus Charge Density Wave Order in Graphene-like Systems

Y. Araki; G. W. Semenoff

doi:10.1103/physrevb.86.121402

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arXiv · 1204.4531

Spin Versus Charge Density Wave Order in Graphene-like Systems

Y. Araki·G. W. Semenoff

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Abstract

A variational technique is used to study sublattice symmetry breaking by strong on-site and nearest neighbor interactions in graphene. When interactions are strong enough to break sublattice symmetry, and with relative strengths characteristic of graphene, a charge density wave Mott insulator is favored over the spin density wave condensates. In the spin density wave condensate we find that introduction of a staggered on-site energy (quasiparticle mass) leads to a splitting of the fermi velocities and mass gaps of the quasiparticle spin states.

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Y. Araki, G. W. Semenoff. 2012-04-20. Spin Versus Charge Density Wave Order in Graphene-like Systems. https://doi.org/10.1103/physrevb.86.121402

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