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arXiv · 1210.4818

Controlling edge states in the Kane-Mele model via edge chirality

Gabriel Autès·Oleg V. Yazyev
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Abstract

We investigate the dependence of band dispersion of the quantum spin Hall effect (QSHE) edge states in the Kane-Mele model on crystallographic orientation of the edges. Band structures of the one-dimensional honeycomb lattice ribbons show the presence of the QSHE edge states at all orientations of the edges given sufficiently strong spin-orbit interactions. We find that the Fermi velocities of the QSHE edge-state bands increase monotonically when the edge orientation changes from zigzag (chirality angle $θ= 0^\circ$) to armchair ($θ= 30^\circ$). We propose a simple analytical model to explain the numerical results.

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Gabriel Autès, Oleg V. Yazyev. 2012-10-17. Controlling edge states in the Kane-Mele model via edge chirality. https://doi.org/10.1002/pssr.201206383

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