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arXiv · 1809.04691

Gate-induced superconductivity in a monolayer topological insulator

Ebrahim Sajadi·Tauno Palomaki·Zaiyao Fei·Wenjin Zhao·Philip Bement·Christian Olsen·Silvia Lüscher·Xiaodong Xu·Joshua A. Folk·David H. Cobden
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Abstract

The layered semimetal WTe_2 has recently been found to be a two-dimensional topological insulator (2D TI) when thinned down to a single monolayer, with conducting helical edge channels. We report here that intrinsic superconductivity can be induced in this monolayer 2D TI by mild electrostatic doping, at temperatures below 1 K. The 2D TI-superconductor transition can be easily driven by applying a just a small gate voltage. This discovery offers new possibilities for gate-controlled devices combining superconductivity and topology, and could provide a basis for quantum information schemes based on topological protection.

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Ebrahim Sajadi, Tauno Palomaki, Zaiyao Fei, Wenjin Zhao, Philip Bement, Christian Olsen, Silvia Lüscher, Xiaodong Xu, Joshua A. Folk, David H. Cobden. 2018-09-12. Gate-induced superconductivity in a monolayer topological insulator. https://doi.org/10.1126/science.aar4426

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