Fully-gapped superconductivity in single crystals of noncentrosymmetric Re${}_6$Zr with broken time-reversal symmetry

Abstract

The noncentrosymmetric superconductor Re${}_6$Zr has attracted much interest due to the observation of broken time-reversal symmetry in the superconducting state. Here we report an investigation of the superconducting gap structure of Re${}_6$Zr single crystals by measuring the magnetic penetration depth shift $\Delta \lambda (T)$ and electronic specific heat $C_e(T)$. $\Delta \lambda (T)$ exhibits an exponential temperature dependence behavior for $T\ll T_c$, which indicates a fully-open superconducting gap. Our analysis shows that a single gap $s$-wave model is sufficient to describe both the superfluid density ${\rho }_s(T)$ and $C_e(T)$ results, with a fitted gap magnitude larger than the weak coupling BCS value, providing evidence for fully-gapped superconductivity in Re${}_6$Zr with moderate coupling.

arXiv comment6 pages, 4 figures

References in corpus (34)

• Time-Reversal Symmetry Breaking Superconductivity in Sr2RuO4
• Superconducting 2D system with lifted spin degeneracy: Mixed singlet-triplet state
• Superconductivty without inversion symmetry: MnSi versus CePt_3Si
• High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
• Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review
• S-wave/spin-triplet order in superconductors without inversion symmetry: Li${}_2$Pd${}_3$B and Li${}_2$Pt${}_3$B
• Phenomenological two-gap model for the specific heat of MgB_2
• 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
• Theoretical aspects of Andreev spectroscopy and tunneling spectroscopy in non-centrosymmetric superconductors: a topical review
• Meissner - London state in superconductors of rectangular cross-section in perpendicular magnetic field
• Superconducting Topological Surface States in Non-centrosymmetric Bulk Superconductor PbTaSe2
• Observation of Time-Reversal Symmetry Breaking in the Non-Centrosymmetric Superconductor Re6Zr
• Beyond Triplet: Unconventional Superconductivity in a Spin-3/2 Topological Semimetal
• Non-unitary triplet pairing in the centrosymmetric superconductor LaNiGa${}_2$
• Dirac Surface States and Nature of Superconductivity in Noncentrosymmetric BiPd
• Multigap superconductivity in sesquicarbides La${}_2$C${}_3$ and Y${}_2$C${}_3$
• Superconductivity of the Ternary Boride Li_2Pd_3B Probed by ^{11}B NMR
• Relativistic analysis of the pairing symmetry of the noncentrosymmetric superconductor LaNiC${}_2$
• Two-gap superconductivity in LaNiGa${}_2$ with non-unitary triplet pairing and even parity gap symmetry
• Evidence of nodal gap structure in the non-centrosymmetric superconductor Y2C3
• Evidence for Novel Pairing State in Noncentrosymmetric Superconductor CePt3Si: 29Si-NMR Knight Shift Study
• Exotic Superconducting Properties in Topological Nodal Semimetal PbTaSe${}_2$
• Observation of the spin-polarized surface state in a noncentrosymmetric superconductor BiPd
• Superconducting and normal-state properties of the noncentrosymmetric superconductor Re6Zr
• Nodeless superconductivity in noncentrosymmetric PbTaSe${}_2$ single crystals
• Multiple nodeless superconducting gaps in noncentrosymmetric superconductor PbTaSe2 with topological bulk nodal lines
• NMR and NQR Studies on Non-centrosymmetric Superconductors Re7B3, LaBiPt, and BiPd
• Complex superconductivity in the noncentrosymmetric compound Re${}_6$Zr
• Anisotropic superconductivity in the noncentrosymmetric BiPd
• Multigap Superconductivity in Y${}_2$C${}_3$: A ${}^{13}$C-NMR Study
• Full-gap superconductivity in non-centrosymmetric Re${}_6$Zr, Re${}_{27}$Zr${}_5$ and Re${}_{24}$Zr${}_5$
• Evidence for nodal superconductivity in quasi-one-dimensional K${}_2$Cr${}_3$As${}_3$
• Multiband Superconductivity in the time reversal symmetry broken superconductor Re6Zr

Cited by in corpus (12)

• Recent progress on superconductors with time-reversal symmetry breaking
• CaPtAs: a new noncentrosymmetric superconductor
• Time-reversal symmetry breaking in Re-based superconductors: Recent developments
• Evidence for the coexistence of time-reversal symmetry breaking and Bardeen-Cooper-Schrieffer-like superconductivity in La${}_7$Pd${}_3$
• High-order Time-Reversal Symmetry Breaking Normal State
• Nodeless superconductivity in noncentrosymmetric LaRhSn
• Spontaneous magnetization in unitary superconductors with time reversal symmetry breaking
• Nodeless superconductivity in the cage-type superconductor Sc5Ru6Sn18 with preserved time-reversal symmetry
• Superconductivity in amorphous RexZr (x ~ 6) thin films
• Quantum muon diffusion and the preservation of time-reversal symmetry in the superconducting state of type-I rhenium
• Nodeless superconductivity in 4H${}_b$-TaS${}_2$ with broken time reversal symmetry
• Pressure induced superconducting dome in LaNiGa2