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arXiv · 1703.04932

$\mu$SR study of noncentrosymmetric superconductor PbTaSe$_2$

M. N. Wilson·A. M. Hallas·Y. Cai·S. Guo·Z. Gong·R. Sankar·F. C. Chou·Y. J. Uemura·G. M. Luke
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Abstract

We present muon spin rotation ($\mu$SR) measurements on the noncentrosymmetric superconductor PbTaSe$_2$. From measurements in an applied transverse field between $H_{c1}$ and $H_{c2}$, we extract the superfluid density as a function of temperature in the vortex state. This data can be fit with a fully gapped two-band model, consistent with previous evidence from ARPES, thermal conductivity, and resistivity. Furthermore, zero field measurements show no evidence for a time reversal symmetry breaking field greater than 0.05~G in the superconducting state. This makes exotic fully gapped spin-triplet states unlikely, and hence we contend that PbTaSe$_2$ is characterized by conventional BCS s-wave superconductivity in multiple bands.

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M. N. Wilson, A. M. Hallas, Y. Cai, S. Guo, Z. Gong, R. Sankar, F. C. Chou, Y. J. Uemura, G. M. Luke. 2017-03-15. $\mu$SR study of noncentrosymmetric superconductor PbTaSe$_2$. https://doi.org/10.1103/physrevb.95.224506

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