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arXiv · 2405.08633

On the superconducting gap structure of the miassite Rh17S15: Nodal or nodeless?

Abstract

Recent penetration depth measurement claimed the observation of unconventional superconductivity in the miassite Rh$_{17}$S$_{15}$ single crystals, evidenced by the linear-in-temperature penetration depth at low temperatures, thereby arguing for the presence of the lines of node in its superconducting gap structure. Here we measure the thermal conductivity of Rh$_{17}$S$_{15}$ single crystals down to 110 mK and up to a field of 8 T ($\simeq 0.4H{\rm_{c2}}$). In marked contrast to the penetration depth measurement, we observe a negligible residual linear term $\kappa_0/T$ in zero field, in line with the nodeless gap structure. The field dependence of $\kappa_0(H)/T$ shows a profile that is more consistent with either a highly anisotropic gap structure or multiple nodeless gaps with significantly different magnitudes. Moreover, first-principles calculations give two electronic bands with complex shape of Fermi surfaces. These results suggest multigap nodeless superconductivity in this multiband Rh$_{17}$S$_{15}$ superconductor.

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J. Y. Nie, C. C. Zhao, C. Q. Xu, B. Li, C. P. Tu, X. Zhang, D. Z. Dai, H. R. Wang, S. Xu, Wenhe Jiao, B. M. Wang, Zhu'an Xu, Xiaofeng Xu, S. Y. Li. 2024-05-14. On the superconducting gap structure of the miassite Rh17S15: Nodal or nodeless?. https://arxiv.org/abs/2405.08633

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