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arXiv · 1511.07717

Nodal superconductivity in FeS: Evidence from quasiparticle heat transport

T. P. Ying·X. F. Lai·X. C. Hong·Y. Xu·L. P. He·J. Zhang·M. X. Wang·Y. J. Yu·F. Q. Huang·S. Y. Li
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Abstract

We report low-temperature heat transport measurements on superconducting iron sulfide FeS with $T_c \approx$ 5 K, which has the same crystal structure and similar electronic band structure to the superconducting iron selenide FeSe. In zero magnetic field, a significant residual linear term $κ_0/T$ is observed. At low field, $κ_0/T$ increases rapidly with the increase of field. These results provide strong evidence for nodal superconducting gap in FeS. We compare it with the sister compound FeSe, and other iron-based superconductors with nodal gap.

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T. P. Ying, X. F. Lai, X. C. Hong, Y. Xu, L. P. He, J. Zhang, M. X. Wang, Y. J. Yu, F. Q. Huang, S. Y. Li. 2016-06-13. Nodal superconductivity in FeS: Evidence from quasiparticle heat transport. https://doi.org/10.1103/physrevb.94.100504

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