Experimental and first-principles studies of superconductivity in topological nodal line semimetal SnTaS2

Abstract

Abstract We report a detailed study of superconductivity in polycrystalline SnTaS2 using electrical transport, magnetization and heat capacity measurements. SnTaS2 crystallizes in centrosymmetric hexagonal structure with space group P 6 3 / m m c . Electrical resistivity, magnetization and specific heat data suggest SnTaS2 to be a weakly coupled, type-II superconductor with T c ≈ 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. Superconductivity in layered SnTaS2 with nodal line topological state makes it a strong candidate to be considered for a 3D topological superconductor.