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arXiv · 1308.6353

Interface-induced Topological Insulator Transition in GaAs/Ge/GaAs Quantum Wells

Dong Zhang·Wenkai Lou·Maosheng Miao·Shou-cheng Zhang·Kai Chang
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Abstract

We demonstrate theoretically that interface engineering can drive Germanium, one of the most commonly-used semiconductors, into topological insulating phase. Utilizing giant electric fields generated by charge accumulation at GaAs/Ge/GaAs opposite semiconductor interfaces and band folding, the new design can reduce the sizable gap in Ge and induce large spin-orbit interaction, which lead to a topological insulator transition. Our work provides a new method on realizing TI in commonly-used semiconductors and suggests a promising approach to integrate it in well developed semiconductor electronic devices.

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Dong Zhang, Wenkai Lou, Maosheng Miao, Shou-cheng Zhang, Kai Chang. 2013-08-29. Interface-induced Topological Insulator Transition in GaAs/Ge/GaAs Quantum Wells. https://doi.org/10.1103/physrevlett.111.156402

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