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arXiv · 1502.05714

Electric and Magnetic Tuning Between the Trivial and Topological Phases in InAs/GaSb Double Quantum Wells

Fanming Qu·Arjan J. A. Beukman·Stevan Nadj-Perge·Michael Wimmer·Binh-Minh Nguyen·Wei Yi·Jacob Thorp·Marko Sokolich·Andrey A. Kiselev·Michael J. Manfra·Charles M. Marcus·Leo P. Kouwenhoven
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Abstract

Among the theoretically predicted two-dimensional topological insulators, InAs/GaSb double quantum wells (DQWs) have a unique double-layered structure with electron and hole gases separated in two layers, which enables tuning of the band alignment via electric and magnetic fields. However, the rich trivial-topological phase diagram has yet to be experimentally explored. We present an in situ and continuous tuning between the trivial and topological insulating phases in InAs/GaSb DQWs through electrical dual-gating. Furthermore, we show that an in-plane magnetic field shifts the electron and hole bands relatively to each other in momentum space, functioning as a powerful tool to discriminate between the topologically distinct states.

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Fanming Qu, Arjan J. A. Beukman, Stevan Nadj-Perge, Michael Wimmer, Binh-Minh Nguyen, Wei Yi, Jacob Thorp, Marko Sokolich, Andrey A. Kiselev, Michael J. Manfra, Charles M. Marcus, Leo P. Kouwenhoven. 2015-02-19. Electric and Magnetic Tuning Between the Trivial and Topological Phases in InAs/GaSb Double Quantum Wells. https://doi.org/10.1103/physrevlett.115.036803

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