Multigap superconductivity in locally non-centrosymmetric SrPtAs: An As nuclear quadrupole resonance investigation

F. Brückner; R. Sarkar; M. Günther; H. Kühne; H. Luetkens; T. Neupert; A. P. Reyes; P. L. Kuhns; P. K. Biswas; T. Stürzer; D. Johrendt; H. -H. Klauss

doi:10.1103/physrevb.90.220503

arXiv · 1312.6166

Multigap superconductivity in locally non-centrosymmetric SrPtAs: An As nuclear quadrupole resonance investigation

F. Brückner·R. Sarkar·M. Günther·H. Kühne·H. Luetkens·T. Neupert·A. P. Reyes·P. L. Kuhns·P. K. Biswas·T. Stürzer·D. Johrendt·H. -H. Klauss

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Abstract

We report detailed $^{75}$As-NQR investigations of the locally non-centrosymmetric superconductor SrPtAs. The spin-lattice relaxation studies prove weakly coupled multi-gap superconductivity. The Hebel-Slichter peak, a hallmark of conventional superconductivity, is strongly suppressed, which points to an unconventional superconducting state. The observed behavior excludes a superconducting order parameter with line nodes and is consistent with proposed $f$-wave and chiral $d$-wave order parameters.

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F. Brückner, R. Sarkar, M. Günther, H. Kühne, H. Luetkens, T. Neupert, A. P. Reyes, P. L. Kuhns, P. K. Biswas, T. Stürzer, D. Johrendt, H. -H. Klauss. 2013-12-20. Multigap superconductivity in locally non-centrosymmetric SrPtAs: An As nuclear quadrupole resonance investigation. https://doi.org/10.1103/physrevb.90.220503

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