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Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells

B. Andrei Bernevig·Taylor L. Hughes·Shou-Cheng Zhang
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Abstract

We show that the Quantum Spin Hall Effect, a state of matter with topological properties distinct from conventional insulators, can be realized in HgTe/CdTe semiconductor quantum wells. By varying the thickness of the quantum well, the electronic state changes from a normal to an "inverted" type at a critical thickness $d_c$. We show that this transition is a topological quantum phase transition between a conventional insulating phase and a phase exhibiting the QSH effect with a single pair of helical edge states. We also discuss the methods for experimental detection of the QSH effect.

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B. Andrei Bernevig, Taylor L. Hughes, Shou-Cheng Zhang. 2006-11-15. Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells. https://doi.org/10.1126/science.1133734

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