Bifurcation of the Edge-State Width in the Two-Dimensional Topological Insulator

Hyeonjin Doh; Gun Sang Jeon

doi:10.1103/physrevb.88.245115

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arXiv · 1306.4001

Bifurcation of the Edge-State Width in the Two-Dimensional Topological Insulator

Hyeonjin Doh·Gun Sang Jeon

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Abstract

We examine the properties of edge states in a two-dimensional topological insulator. Based on the Kane-Mele model, we derive two coupled equations for the energy and the effective width of edge states at a given momentum in a semi-infinite honeycomb lattice with a zigzag boundary. It is revealed that, in a one-dimensional Brillouin zone, the edge states merge into the continuous bands of the bulk states through a bifurcation of the edge-state width. We discuss the implications of the results to the experiments in monolayer or thin films of topological insulators.

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Hyeonjin Doh, Gun Sang Jeon. 2013-06-17. Bifurcation of the Edge-State Width in the Two-Dimensional Topological Insulator. https://doi.org/10.1103/physrevb.88.245115

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