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arXiv · 1208.3023

Bound States of Conical Singularities in Graphene-Based Topological Insulators

Andreas Rüegg·Chungwei Lin
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Abstract

We investigate the electronic structure induced by wedge-disclinations (conical singularities) in a honeycomb lattice model realizing Chern numbers $\gamma=\pm 1$. We establish a correspondence between the bound state of (i) an isolated $\Phi_0/2$-flux, (ii) an isolated pentagon $(n=1)$ or heptagon $(n=-1)$ defect with an external flux of magnitude $n\gamma \Phi_0/4$ through the center and (iii) an isolated square or octagon defect without external flux, where $\Phi_0=h/e$ is the flux quantum. Due to the above correspondence, the existence of isolated electronic states bound to the disclinations is robust against various perturbations. These results are also generalized to graphene-based time-reversal invariant topological insulators.

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Andreas Rüegg, Chungwei Lin. 2012-08-15. Bound States of Conical Singularities in Graphene-Based Topological Insulators. https://doi.org/10.1103/physrevlett.110.046401

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