Topological superconductivity is an exotic phenomenon due to the symmetry-protected topological surface state, in which a quantum system has an energy gap in the bulk but supports gapless excitations confined to its boundary. Symmetries including central and time-reversal (TRS), along with their relations with topology, are crucial for topological superconductivity. We report muon spin relaxation/rotation (μSR) experiments on a topological noncentrosymmetric superconductor PbTaSe2 to study its TRS and gap symmetry. Zero-field μSR experiments indicate the absence of internal magnetic field in the superconducting state, consistent with previous μSR results. Furthermore, transverse-field μSR measurements reveals that the superconducting gap of PbTaSe2 is an isotropic three-dimensional fully-gapped single-band. The fully-gapped results can help understand the pairing mechanism and further classify the topological superconductivity in this system.
@article{arxiv.2112.05970,
title = {Muon spin rotation and relaxation study on topological noncentrosymmetric superconductor PbTaSe$_2$},
author = {Z. H. Zhu and C. Tan and J. Zhang and P. K. Biswas and A. D. Hillier and M. X. Wang and Y. X. Yang and C. S. Chen and Z. F. Ding and S. Y. Li and L. Shu},
journal= {arXiv preprint arXiv:2112.05970},
year = {2022}
}