High-resolution magnetic penetration depth and inhomogeneities in locally noncentrosymmetric SrPtAs

作者:Landaeta J F*; Taylor S V; Bonalde I; Rojas C; Nishikubo Y; Kudo K; Nohara M
来源:PHYSICAL REVIEW B, 2016, 93(6): 064504.
DOI:10.1103/PhysRevB.93.064504

摘要

We present a magnetic-penetration-depth study on polycrystalline and granular samples of SrPtAs, a pnictide superconductor with a hexagonal structure containing PtAs layers that individually break inversion symmetry (local noncentrosymmetry). Compact samples show a clear-cut s-wave-type BCS behavior, which we consider to be the intrinsic penetration depth of SrPtAs. Granular samples display a sample-dependent second diamagnetic drop, attributed to the intergrain coupling. Our experimental results point to a nodeless isotropic superconducting energy gap in SrPtAs, which puts strong constraints on the driven mechanism for superconductivity and the order parameter symmetry of this compound.

  • 出版日期2016-2-2