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arXiv · 1312.3229

Low field magnetic response of the non-centrosymmetric superconductor YPtBi

T. V. Bay·M. Jackson·C. Paulsen·C. Baines·A. Amato·T. Orvis·M. C. Aronson·Y. K. Huang·A. de Visser
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Abstract

The low-field magnetic response of the non-centrosymmetric superconductor YPtBi ($T_c =0.77$ K) is investigated. Ac-susceptibility and dc-magnetization measurements provide solid evidence for bulk superconductivity with a volume fraction of $\sim 70\%$. The lower critical field is surprisingly small: $B_{c1} = 0.008$ mT $(T \rightarrow 0)$. Muon spin rotation experiments in a transverse magnetic field of 0.01 T show a weak increase of the Gaussian damping rate $σ_{TF}$ below $T_c$, which yields a London penetration depth $λ= 1.6 \pm 0.2~ μ$m. The zero-field Kubo-Toyabe relaxation rate $σ_{KT}$ equals $0.129 \pm 0.004~μ$s$^{-1}$ and does not show a significant change below $T_c$. This puts an upper bound of 0.04 mT on the spontaneous magnetic field associated with a possible odd-parity component in the superconducting order parameter.

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T. V. Bay, M. Jackson, C. Paulsen, C. Baines, A. Amato, T. Orvis, M. C. Aronson, Y. K. Huang, A. de Visser. 2013-12-11. Low field magnetic response of the non-centrosymmetric superconductor YPtBi. https://doi.org/10.1016/j.ssc.2013.12.011

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