Nodeless superconductivity in noncentrosymmetric LaRhSn

Z. Y. Nie; J. W. Shu; A. Wang; H. Su; W. Y. Duan; A. D. Hillier; D. T. Adroja; P. K. Biswas; T. Takabatake; M. Smidman; H. Q. Yuan

doi:10.1103/physrevb.105.134523

arXiv · 2301.01467

Nodeless superconductivity in noncentrosymmetric LaRhSn

Z. Y. Nie·J. W. Shu·A. Wang·H. Su·W. Y. Duan·A. D. Hillier·D. T. Adroja·P. K. Biswas·T. Takabatake·M. Smidman·H. Q. Yuan

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Abstract

The superconducting order parameter of the noncentrosymmetric superconductor LaRhSn is investigated by means of low temperature measurements of the specific heat, muon-spin relaxation/rotation ($\mu$SR) and the tunnel-diode oscillator (TDO) based method. The specific heat and magnetic penetration depth [$\lambda(T)$] show an exponentially activated temperature dependence, demonstrating fully gapped superconductivity in LaRhSn. The temperature dependence of $\lambda^{-2}(T)$ deduced from the TDO based method and $\mu$SR show nearly identical behavior, which can be well described by a single-gap $s$-wave model, with a zero temperature gap value of $\Delta(0)=1.77(4)k_BT_c$. The zero-field $\mu$SR spectra do not show detectable changes upon cooling below $T_c$, and therefore there is no evidence for time-reversal-symmetry breaking in the superconducting state.

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Z. Y. Nie, J. W. Shu, A. Wang, H. Su, W. Y. Duan, A. D. Hillier, D. T. Adroja, P. K. Biswas, T. Takabatake, M. Smidman, H. Q. Yuan. 2023-01-04. Nodeless superconductivity in noncentrosymmetric LaRhSn. https://doi.org/10.1103/physrevb.105.134523

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