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arXiv · 0803.1050

Interactions and magnetism in graphene boundary states

B. Wunsch·T. Stauber·F. Sols·F. Guinea
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Abstract

We analyze interaction effects on boundary states of single layer graphene. Near a half filled band, both short and long-ranged interactions lead to a fully spin polarized configuration. In addition, the band of boundary states acquires a finite dispersion as function of the momentum parallel to the edge, induced by the interactions. Away from half filling the wavefunction develops charge correlations similar to those in a Wigner crystal, and the spin strongly alternates with the occupation of the boundary states. For certain fillings the ground state has a finite linear momentum, leading to the formation of persistent currents.

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B. Wunsch, T. Stauber, F. Sols, F. Guinea. 2008-03-07. Interactions and magnetism in graphene boundary states. https://doi.org/10.1103/physrevlett.101.036803

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