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arXiv · 1002.3155

Wormhole Effect in a Strong Topological Insulator

G. Rosenberg·H. -M. Guo·M. Franz
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Abstract

An infinitely thin solenoid carrying magnetic flux Phi (a `Dirac string') inserted into an ordinary band insulator has no significant effect on the spectrum of electrons. In a strong topological insulator, remarkably, such a solenoid carries protected gapless one-dimensional fermionic modes when Phi=hc/2e. These modes are spin-filtered and represent a distinct bulk manifestation of the topologically non-trivial insulator. We establish this `wormhole' effect by both general qualitative considerations and by numerical calculations within a minimal lattice model. We also discuss the possibility of experimental observation of a closely related effect in artificially engineered nanostructures.

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G. Rosenberg, H. -M. Guo, M. Franz. 2010-02-16. Wormhole Effect in a Strong Topological Insulator. https://doi.org/10.1103/physrevb.82.041104

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