Muon-spin rotation study of the in-plane magnetic penetration depth of FeSe_0.85: evidence for nodeless superconductivity

R. Khasanov; K. Conder; E. Pomjakushina; A. Amato; C. Baines; Z. Bukowski; J. Karpinski; S. Katrych; H. -H. Klauss; H. Luetkens; A. Shengelaya; N. D. Zhigadlo

arXiv · 0810.1716

Muon-spin rotation study of the in-plane magnetic penetration depth of FeSe_0.85: evidence for nodeless superconductivity

R. Khasanov·K. Conder·E. Pomjakushina·A. Amato·C. Baines·Z. Bukowski·J. Karpinski·S. Katrych·H. -H. Klauss·H. Luetkens·A. Shengelaya·N. D. Zhigadlo

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Abstract

The in-plane magnetic penetration depth λ_{ab} of the iron selenide superconductor with the nominal composition FeSe_0.85 was studied by means of muon-spin rotation. The measurements of λ_{ab}^{-2}(T) are inconsistent with the presence of nodes in the gap as well as with a simple isotropic s-wave type of the order parameter, but can be equally well described within a two-gap (s+s) and an anisotropic s-wave gap picture. This implies that the superconducting energy gap in FeSe_0.85 contains no nodes.

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R. Khasanov, K. Conder, E. Pomjakushina, A. Amato, C. Baines, Z. Bukowski, J. Karpinski, S. Katrych, H. -H. Klauss, H. Luetkens, A. Shengelaya, N. D. Zhigadlo. 2008-10-09. Muon-spin rotation study of the in-plane magnetic penetration depth of FeSe_0.85: evidence for nodeless superconductivity. https://arxiv.org/abs/0810.1716

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