Abstract
We have employed muon spin relaxation and rotation to investigate the superconducting properties of the noncentrosymmetric superconductor . Measurements of single-crystal specimens confirm the development of a robust superconducting state below with a ground-state magnetic penetration depth of and a coherence length of . The temperature evolution of the superfluid density indicates a nodeless superconducting gap structure dominated by an isotropic spin-singlet component in the dirty limit with a carrier density of as determined by Hall resistance measurements. We find no evidence of spontaneous time-reversal symmetry breaking in the superconducting state within an accuracy of 0.05 G. These observations suggest that the influence of any spin-triplet pairing component or multiple gap structure associated with noncentrosymmetric physics is very weak or entirely absent in .
- Received 30 August 2014
- Revised 27 November 2014
DOI:https://doi.org/10.1103/PhysRevB.91.014511
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