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arXiv · 0912.0471

Evolution of two-gap behavior of the superconductor FeSe_1-x

R. Khasanov·M. Bendele·A. Amato·K. Conder·H. Keller·H. -H. Klauss·H. Luetkens·E. Pomjakushina
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Abstract

The superfluid density, ρ_s, of the iron chalcogenide superconductor, FeSe_1-x, was studied as a function of pressure by means of muon-spin rotation. The zero-temperature value of ρ_s increases with increasing transition temperature T_c (increasing pressure) following the tendency observed for various Fe-based and cuprate superconductors. The analysis of ρ_s(T) within the two-gap scheme reveals that the effect on both, T_c and ρ_s(0), is entirely determined by the band(s) where the large superconducting gap develops, while the band(s) with the small gap become practically unaffected.

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R. Khasanov, M. Bendele, A. Amato, K. Conder, H. Keller, H. -H. Klauss, H. Luetkens, E. Pomjakushina. 2009-12-02. Evolution of two-gap behavior of the superconductor FeSe_1-x. https://doi.org/10.1103/physrevlett.104.087004

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