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arXiv · 2203.16458

Time-reversal-symmetry Breaking in the Superconducting State of ScS

Arushi·R. K. Kushwaha·D. Singh·A. D. Hillier·M. S. Scheurer·R. P. Singh
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Abstract

We have studied the electronic properties of ScS, a transition-metal monochalcogenide with rocksalt crystal structure, using magnetization, specific heat, transport, and muon spin rotation/relaxation ($\mu$SR) measurements. All measurements confirm the bulk superconducting in ScS with a transition temperature of $T_{C}$ = 5.1(5) K. Specific heat together with transverse-field $\mu$SR measurements indicate a full gap, while our zero-field $\mu$SR study reveals the presence of spontaneous static or quasi-static magnetic fields emerging when entering the superconducting state. We discuss various possible microscopic origins of the observed time-reversal-symmetry breaking. As none of them can be readily reconciled with a conventional pairing mechanism, this introduces ScS as a novel candidate material for unconventional superconductivity.

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Arushi, R. K. Kushwaha, D. Singh, A. D. Hillier, M. S. Scheurer, R. P. Singh. 2022-03-30. Time-reversal-symmetry Breaking in the Superconducting State of ScS. https://doi.org/10.1103/physrevb.106.l020504

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