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arXiv · 0810.2101

Edge states in Graphene: from gapped flat band to gapless chiral modes

Wang Yao·Shengyuan A. Yang·Qian Niu
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Abstract

We study edge-states in graphene systems where a bulk energy gap is opened by inversion symmetry breaking. We find that the edge-bands dispersion can be controlled by potentials applied on the boundary with unit cell length scale. Under certain boundary potentials, gapless edge-states with valley-dependent velocity are found, exactly analogous to the spin-dependent gapless chiral edge-states in quantum spin Hall systems. The connection of the edge-states to bulk topological properties is revealed.

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Wang Yao, Shengyuan A. Yang, Qian Niu. 2008-10-14. Edge states in Graphene: from gapped flat band to gapless chiral modes. https://doi.org/10.1103/physrevlett.102.096801

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