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Title: Electrically tunable low-density superconductivity in a monolayer topological insulator

Turning on superconductivity in a topologically nontrivial insulator may provide a route to search for non-Abelian topological states. However, existing demonstrations of superconductor-insulator switches have involved only topologically trivial systems. Here we report reversible, in situ electrostatic on-off switching of superconductivity in the recently established quantum spin Hall insulator monolayer tungsten ditelluride (WTe2). Fabricated into a van der Waals field-effect transistor, the monolayer’s ground state can be continuously gate-tuned from the topological insulating to the superconducting state, with critical temperaturesTcup to ~1 kelvin. Our results establish monolayer WTe2as a material platform for engineering nanodevices that combine superconducting and topological phases of matter.

 
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NSF-PAR ID:
10080079
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science
Volume:
362
Issue:
6417
ISSN:
0036-8075
Page Range / eLocation ID:
p. 926-929
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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