NbReSi: A Noncentrosymetric Superconductor with Large Upper Critical Field

Abstract

We report the discovery of superconductivity in noncentrosymmetric NbReSi, which crystallizes in a hexagonal ZrNiAl-type crystal structure with space group $P\bar{6}2m$ (No.~189). Bulk superconductivity, with $T_c$ = 6.5 K was characterized via electrical-resistivity, magnetization, and heat-capacity measurements. The low-temperature electronic specific heat suggests a fully gapped superconducting state in NbReSi, while a large upper critical field of ${\mu }_0{H}_{c2}(0)$ $\sim$ 12.6 T is obtained, which is comparable to the weak-coupling Pauli limit. The electronic band-structure calculations show that the density of states at the Fermi level are dominated by Re and Nb $d$-orbitals, with a sizeable band splitting induced by the antisymmetric spin-orbit coupling. NbReSi represents another candidate material for revealing the puzzle of time-reversal symmetry breaking observed in some Re-based superconductors and its relation to the lack of inversion symmetry.

7 pages, 6 figures; accepted by Phys. Rev. Materials

References in corpus (20)

• Evidence for time-reversal symmetry breaking in the non-centrosymmetric superconductor LaNiC${}_2$
• Spin Triplet Superconducting State due to Broken Inversion Symmetry in Li_2Pt_3B
• Multigap superconductivity in sesquicarbides La${}_2$C${}_3$ and Y${}_2$C${}_3$
• Time-reversal symmetry breaking in noncentrosymmetric superconductor Re6Hf:further evidence for unconventional behaviour in the alpha-Mn family of materials
• Anisotropic $H_{c2}$, thermodynamic and transport measurements, and pressure dependence of $T_c$ in K${}_2$Cr${}_3$As${}_3$ single crystals
• Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs
• Nodeless superconductivity and time-reversal symmetry breaking in the noncentrosymmetric superconductor Re24Ti5
• Superconducting and normal-state properties of the noncentrosymmetric superconductor Re6Zr
• Comparative study of the centrosymmetric and non-centrosymmetric superconducting phases of Re3W using muon-spin spectroscopy and heat capacity measurements
• Upper critical field in noncentrosymmetric superconductors
• Multigap Superconductivity in Y${}_2$C${}_3$: A ${}^{13}$C-NMR Study
• CaPtAs: a new noncentrosymmetric superconductor
• Time-reversal symmetry breaking and multigap superconductivity in the noncentrosymmetric superconductor La${}_7$Ni${}_3$
• Probing the superconducting gap structure in the noncentrosymmetric topological superconductor ZrRuAs
• Unconventional superconducting properties of noncentrosymmetric Re5.5Ta
• Time-reversal symmetry breaking in Re-based superconductors: Recent developments
• Superconducting properties of the non-centrosymmetric Superconductors TaXSi (X= Re, Ru)
• Nodeless superconductivity in the centro- and noncentrosymmetric rhenium-boron superconductors
• Fully gapped superconductivity with preserved time reversal symmetry in noncentrosymmetric LaPdIn
• Evidence for the coexistence of time-reversal symmetry breaking and Bardeen-Cooper-Schrieffer-like superconductivity in La${}_7$Pd${}_3$