family

Nodal line semimetals are novel quantum states of matter, hosting topological nodal rings in the bulk band structures. Among the nodal line semimetals, PbTaSe₂ family without the inversion symmetry in the crystal structure has been reported to be superconducting, and can be a promising platform for the study of topological superconductivity [1,2]. Here we present the superconducting properties of single crystals of PbTaSe₂ family. Our resistivity measurements under high magnetic fields reveal the unusual temperature dependence and magnitude of the upper critical field in this family, strikingly distinct from those for conventional BCS-type superconductors. Compering theoretical models, we will discuss the possible superconducting pairing symmetry realized in this family.


[1] M.N. Ali et al., Phys. Rev. B 89 020505 (2014).
[2] G. Bian et al., Nat. Commun. 7, 10556 (2016).