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arXiv · 1010.6046

Magnetism and Disorder Effects on muSR Measurements of the Magnetic Penetration Depth in Iron-Based Superconductors

J. E. Sonier·W. Huang·C. V. Kaiser·C. Cochrane·V. Pacradouni·S. A. Sabok-Sayr·M. D. Lumsden·B. C. Sales·M. A. McGuire·A. S. Sefat·D. Mandrus
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Abstract

It is shown that attempts to accurately deduce the magnetic penetration depth of overdoped BaFe_{1.82}Co_{0.18}As2 single crystals by transverse-field muon spin rotation (TF-muSR) are thwarted by field-induced magnetic order and strong vortex-lattice disorder. We explain how substantial deviations from the magnetic field distribution of a nearly perfect vortex lattice by one or both of these factors is also significant for other iron-based superconductors, and this introduces considerable uncertainty in the values of the magnetic penetration depth obtained by TF-muSR.

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J. E. Sonier, W. Huang, C. V. Kaiser, C. Cochrane, V. Pacradouni, S. A. Sabok-Sayr, M. D. Lumsden, B. C. Sales, M. A. McGuire, A. S. Sefat, D. Mandrus. 2010-10-28. Magnetism and Disorder Effects on muSR Measurements of the Magnetic Penetration Depth in Iron-Based Superconductors. https://doi.org/10.1103/physrevlett.106.127002

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