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arXiv · 1410.7621

Modification and Control of Topological Insulator Surface States Using Surface Disorder

Vincent Sacksteder·Tomi Ohtsuki·Koji Kobayashi
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Abstract

We numerically demonstrate a practical means of systematically controlling topological transport on the surface of a three dimensional topological insulator, by introducing strong disorder in a layer of depth $d$ extending inward from the surface of the topological insulator. The dependence on $d$ of the density of states, conductance, scattering time, scattering length, diffusion constant, and mean Fermi velocity are investigated. The proposed control via disorder depth $d$ requires that the disorder strength be near the large value which is necessary to drive the TI into the non-topological phase. If $d$ is patterned using masks, gates, ion implantation, etc., then integrated circuits may be fabricated. This technique will be useful for experiments and for device engineering.

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Vincent Sacksteder, Tomi Ohtsuki, Koji Kobayashi. 2015-05-16. Modification and Control of Topological Insulator Surface States Using Surface Disorder. https://doi.org/10.1103/physrevapplied.3.064006

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