Fully gapped spin-singlet superconductivity in noncentrosymmetric PbTaSe${}_2$ : ${}^{207}$Pb-NMR

Abstract

We report the ${}^{207}$Pb nuclear magnetic resonance (NMR) measurements on polycrystalline sample of PbTaSe${}_2$ with noncentrosymmetric crystal structure and topological electronic band. The nuclear spin-lattice relaxation rate $1/T_1$ shows a suppressed coherence peak below the superconducting transition temperature $T_{\mathrm{c}}$ = 4.05 K and decreases as an exponential function of temperature. The penetration depth derived from the NMR spectrum is almost temperature independent below $T$ = 0.7 $T_{\mathrm{c}}$. The Knight shift $K$ decreases below $T_{\mathrm{c}}$. These results suggest spin-singlet superconductivity with a fully-opened gap $2\Delta =3.5$ $k_{\mathrm{B}}{T}_{\mathrm{c}}$ in PbTaSe${}_2$.

12 pages, 5 figures

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Cited by in corpus (8)

• Evidence for nematic superconductivity of topological surface states in PbTaSe2
• Antiferromagnetic spin fluctuations and superconductivity in NbRh${}_2$B${}_2$ and TaRh${}_2$B${}_2$ with a chiral crystal structure
• Anomalous Nernst Effect in Nonmagnetic Nodal Line Semimetal PbTaSe${}_2$
• Fully gapped superconductivity without sign reversal in the topological superconductor PbTaSe${}_2$
• ${}^{181}$Ta Nuclear quadrupole resonance study of non-centrosymmetric superconductor PbTaSe${}_2$
• Observation of multigap and coherence peak in the noncentrosymmetric superconductor CaPtAs: ${}^{75}$As nuclear quadrupole resonance measurement
• Muon spin rotation and relaxation study on topological noncentrosymmetric superconductor PbTaSe${}_2$
• Theoretical analysis of anisotropic upper critical field of superconductivity in nodal-line semimetals