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arXiv · 1005.3912

Well-localized edge states in two-dimensional topological insulators: ultrathin Bi films

M. Wada·S. Murakami·F. Freimuth·G. Bihlmayer
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Abstract

We theoretically study the generic behavior of the penetration depth of the edge states in two-dimensional quantum spin Hall systems. We found that the momentum-space width of the edge-state dispersion scales with the inverse of the penetration depth. As an example of well-localized edge states, we take the Bi(111) ultrathin film. Its edge states are found to extend almost over the whole Brillouin zone. Correspondingly, the bismuth (111) 1-bilayer system is proposed to have well-localized edge states in contrast to the HgTe quantum well.

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M. Wada, S. Murakami, F. Freimuth, G. Bihlmayer. 2010-05-21. Well-localized edge states in two-dimensional topological insulators: ultrathin Bi films. https://doi.org/10.1103/physrevb.83.121310

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