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arXiv · 1302.5716

Design principles for HgTe based topological insulator devices

Parijat Sengupta·Tillmann Kubis·Yaohua Tan·Michael Povolotskyi·Gerhard Klimeck
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Abstract

The topological insulator properties of CdTe/HgTe/CdTe quantum wells are theoretically studied. The CdTe/HgTe/CdTe quantum well behaves as a topological insulator beyond a critical well width dimension. It is shown that if the barrier(CdTe) and well-region(HgTe) are altered by replacing them with the alloy Cd$_{x}% $Hg$_{1-x}$Te of various stoichiometries, the critical width can be changed.The critical quantum well width is shown to depend on temperature, applied stress, growth directions and external electric fields. Based on these results, a novel device concept is proposed that allows to switch between a normal semiconducting and topological insulator state through application of moderate external electric fields.

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Parijat Sengupta, Tillmann Kubis, Yaohua Tan, Michael Povolotskyi, Gerhard Klimeck. 2013-02-22. Design principles for HgTe based topological insulator devices. https://doi.org/10.1063/1.4813877

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