Observation of an edge supercurrent in the Weyl superconductor MoTe$_2$

TL;DR

This paper reports the detection of a robust edge supercurrent in the Weyl superconductor MoTe2, characterized by unique oscillation patterns and area dependence, advancing understanding of topological superconductivity.

Contribution

It provides the first experimental observation of an edge supercurrent in a Weyl superconductor, revealing distinct oscillation modes and symmetry-breaking features.

Findings

Edge supercurrent observed in MoTe2 superconductor

Fast-mode oscillation frequency depends on crystal area

Broken symmetry in excitation branches detected

Abstract

Edge supercurrents in superconductors have long been an elusive target. Interest in them has reappeared in the context of topological superconductivity. We report the observation of a robust edge supercurrent in the Weyl superconductor MoTe2. In a magnetic field B, fluxoid quantization generates a periodic modulation of the edge condensate observable as a "fast-mode" oscillation of the critical current Ic versus B. Remarkably, 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 which display an unusual broken symmetry.