Probing the superconducting gap structure in the noncentrosymmetric topological superconductor ZrRuAs

Debarchan Das; D. T. Adroja; M. R. Lees; R. W. Taylor; Z. S. Bishnoi; V. K. Anand; A. Bhattacharyya; Z. Guguchia; C. Baines; H. Luetkens; G. B. G. Stenning; Lei Duan; Xiancheng Wang; Changqing Jin

doi:10.1103/physrevb.103.144516

arXiv · 2101.08234

Probing the superconducting gap structure in the noncentrosymmetric topological superconductor ZrRuAs

Debarchan Das·D. T. Adroja·M. R. Lees·R. W. Taylor·Z. S. Bishnoi·V. K. Anand·A. Bhattacharyya·Z. Guguchia·C. Baines·H. Luetkens·G. B. G. Stenning·Lei Duan·Xiancheng Wang·Changqing Jin

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Abstract

The superconducting gap structure of a topological crystalline insulator (TCI) candidate ZrRuAs ($T^{\rm on}_{\rm c}$ = 7.9(1) K) with a noncentrosymmetric crystal structure has been investigated using muon spin rotation/relaxation ($\mu$SR) measurements in transverse-field (TF) and zero-field (ZF) geometries. We also present the results of magnetization, electrical resistivity and heat capacity measurements on ZrRuAs, which reveal bulk superconductivity below 7.9~K. The temperature dependence of the effective penetration depth obtained from the analysis of the TF-$\mu$SR spectra below $T_{\rm c}$ is well described by an isotropic $s$-wave gap model as also inferred from an analysis of the heat capacity in the superconducting state. ZF $\mu$SR data do not show any significant change in the muon spin relaxation rate above and below the superconducting transition temperature indicating that time-reversal symmetry is preserved in the superconducting state of this material.

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Debarchan Das, D. T. Adroja, M. R. Lees, R. W. Taylor, Z. S. Bishnoi, V. K. Anand, A. Bhattacharyya, Z. Guguchia, C. Baines, H. Luetkens, G. B. G. Stenning, Lei Duan, Xiancheng Wang, Changqing Jin. 2021-01-20. Probing the superconducting gap structure in the noncentrosymmetric topological superconductor ZrRuAs. https://doi.org/10.1103/physrevb.103.144516

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