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arXiv · 1211.2088

Protection of the surface states in topological insulators: Berry phase perspective

Ken-Ichiro Imura·Yositake Takane
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Abstract

The metallic surface state of a topological insulator (TI) is not only topologically protected, but exhibits a remarkable property of inducing an effective vector potential on curved surfaces. For an electron in the surface state of a spherical or a cylindrical TI (TI nanoparticle or nanowire) a pseudo-magnetic monopole or a fictitious solenoid is effectively induced, encoding the geometry of the system. Here, by taking an example of a hyperbolic surface we demonstrate that as a consequence of this property stemming from its active spin degree of freedom, the surface state is by itself topologically protected.

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Ken-Ichiro Imura, Yositake Takane. 2013-02-28. Protection of the surface states in topological insulators: Berry phase perspective. https://doi.org/10.1103/physrevb.87.205409

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