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arXiv · 1108.1638

Chiral Symmetry and Electron-Electron Interaction in Many-Body Gap Formation in Graphene

Y. Hamamoto·Y. Hatsugai·H. Aoki
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Abstract

We study a many-body ground state of graphene in perpendicular magnetic fields. Chiral symmetry in graphene enables us to determine the many-body ground state, which turns out to be a doubly degenerate chiral condensate for the half-filled (undoped) case. In the ground state a prominent charge accumulation emerges along zigzag edges. We also show that gapless excitations are absent despite the presence of the robust edge modes, which is consistent with the Chern number C = 0.

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Y. Hamamoto, Y. Hatsugai, H. Aoki. 2011-08-08. Chiral Symmetry and Electron-Electron Interaction in Many-Body Gap Formation in Graphene. https://doi.org/10.1088/1742-6596%2F400%2F4%2F042015

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