Evidence of fully gapped superconductivity in NbReSi: A combined μsR and NMR study
- Journal Article
We report a comprehensive study of the noncentrosymmetric NbReSi superconductor by means of muon-spin rotation and relaxation (μSR) and nuclear magnetic resonance (NMR) techniques. NbReSi is a bulk superconductor with Tc=6.5 K, characterized by a large upper critical field, which exceeds the Pauli limit. Both the superfluid density ρsc(T) (determined via transverse-field μSR) and the spin-lattice relaxation rate T1-1(T) (determined via NMR) suggest a nodeless superconductivity (SC) in NbReSi. We also find signatures of multigap SC, here evidenced by the field-dependent muon-spin relaxation rate and the electronic specific-heat coefficient. The absence of spontaneous magnetic fields below Tc, as evinced from zero-field μSR measurements, indicates a preserved time-reversal symmetry in the superconducting state of NbReSi. Finally, we discuss possible reasons for the unusually large upper critical field of NbReSi, most likely arising from its anisotropic crystal structure. Show more
Journal / seriesPhysical Review B
Pages / Article No.
PublisherAmerican Physical Society
MoreShow all metadata