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arXiv · 1303.0661

Perfectly conducting channel on the dark surface of weak topological insulators

Yukinori Yoshimura·Akihiko Matsumoto·Yositake Takane·Ken-Ichiro Imura
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Abstract

A weak topological insulator (WTI) bears, generally, an even number of Dirac cones on its surface; they are susceptible of doubling, while on the surface of a certain orientation it shows no Dirac cone. On this "dark" surface of a WTI, we predict the existence of a single pair of isolated 1D perfectly conducting channels that forms either a closed loop or a segment of a line. The former is associated typically with a single atomic-layer-thick island formed on the dark surface, while the latter is shown to be the consequence of a pair of crystal (screw) dislocations terminating on the dark surface.

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Yukinori Yoshimura, Akihiko Matsumoto, Yositake Takane, Ken-Ichiro Imura. 2013-03-04. Perfectly conducting channel on the dark surface of weak topological insulators. https://doi.org/10.1103/physrevb.88.045408

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