Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs

T. Shang, M. Smidman, A. Wang, Lieh-Jeng Chang, C. Baines, M. K. Lee, Z. Y. Nie, G. M. Pang, W. Xie, W. B. Jiang, M. Shi, M. Medarde, T. Shiroka, H. Q. Yuan

研究成果: Article

2 引文 斯高帕斯(Scopus)

摘要

By employing a series of experimental techniques, we provide clear evidence that CaPtAs represents a rare example of a noncentrosymmetric superconductor which simultaneously exhibits nodes in the superconducting gap and broken time-reversal symmetry (TRS) in its superconducting state (below Tc≈1.5 K). Unlike in fully gapped superconductors, the magnetic penetration depth λ(T) does not saturate at low temperatures, but instead it shows a T2 dependence, characteristic of gap nodes. Both the superfluid density and the electronic specific heat are best described by a two-gap model comprising of a nodeless gap and a gap with nodes, rather than by single-band models. At the same time, zero-field muon-spin relaxation spectra exhibit increased relaxation rates below the onset of superconductivity, implying that TRS is broken in the superconducting state of CaPtAs, hence indicating its unconventional nature. Our observations suggest CaPtAs to be a new remarkable material that links two apparently disparate classes, that of TRS-breaking correlated magnetic superconductors with nodal gaps and the weakly correlated noncentrosymmetric superconductors with broken TRS, normally exhibiting only a fully gapped behavior.

原文English
文章編號207001
期刊Physical review letters
124
發行號20
DOIs
出版狀態Published - 2020 五月 22

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

指紋 深入研究「Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs」主題。共同形成了獨特的指紋。

  • 引用此

    Shang, T., Smidman, M., Wang, A., Chang, L-J., Baines, C., Lee, M. K., Nie, Z. Y., Pang, G. M., Xie, W., Jiang, W. B., Shi, M., Medarde, M., Shiroka, T., & Yuan, H. Q. (2020). Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs. Physical review letters, 124(20), [207001]. https://doi.org/10.1103/PhysRevLett.124.207001