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arXiv · 2201.12551

Experimental and first-principles studies of superconductivity in topological nodal line semimetal SnTaS$_2$

Soumen Ash·Moumita Naskar·Ravi Shankar P. N.·Nityasagar Jena·A. Sundaresan·Ashok Kumar Ganguli
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Abstract

We report a detailed study of superconductivity in polycrystalline SnTaS$_2$ using electrical transport, magnetization and heat capacity measurements. SnTaS$_2$ crystallizes in centrosymmetric hexagonal structure with space group $P6_3/mmc$. Electrical resistivity, magnetization and specific heat data suggest SnTaS$_2$ to be a weakly coupled, type-II superconductor with $T_c \approx$ 2.8 K. First-principles calculations show signature for nodal line topology in the electronic band structure, protected by the spatial-inversion and time-reversal symmetries, that strongly gapped out by the inclusion of spin-orbit coupling (SOC). Superconductivity in layered SnTaS$_2$ with nodal line topological state makes it a strong candidate to be considered for a 3D topological superconductor.

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Soumen Ash, Moumita Naskar, Ravi Shankar P. N., Nityasagar Jena, A. Sundaresan, Ashok Kumar Ganguli. 2022-01-29. Experimental and first-principles studies of superconductivity in topological nodal line semimetal SnTaS$_2$. https://doi.org/10.1088/1361-6668/ac5aa8

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