Evidence for an edge supercurrent in the Weyl superconductor MoTe 2

Edge supercurrents in superconductors have long been an elusive target. Interest in them has reappeared in the context of topological superconductivity. We report evidence for the existence of a robust edge supercurrent in the Weyl superconductor molybdenum ditelluride (MoTe2). In a magnetic fieldB, fluxoid quantization generates a periodic modulation of the edge condensate observable as a “fast-mode” oscillation of the critical currentIcversusB. The fast-mode frequency is distinct from the conventional Fraunhofer oscillation displayed by the bulk supercurrent. We confirm that the fast-mode frequency increases with crystal area as expected for an edge supercurrent. In addition, weak excitation branches are resolved that display an unusual broken symmetry.

Authors:
;  ;  ;  ;  ;
Publication Date:
NSF-PAR ID:
10147465
Journal Name:
Science
Volume:
368
Issue:
6490
Page Range or eLocation-ID:
p. 534-537
ISSN:
0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)
National Science Foundation
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