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arXiv · 1401.7780

Cooperative order in the weakly magnetic domain of LaFeAsO$_{1-x}$F$_{x}$ near the doping phase boundary

M. Hiraishi·R. Kadono·M. Miyazaki·I. Yamauchi·A. Koda·K. M. Kojima·M. Ishikado·S. Wakimoto·S. Shamoto
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Abstract

Spatial phase separation into mesoscopic domains of non-magnetic [superconducting (SC) below Tc = 25.5 K] and two kinds of magnetic phases, one showing disordered spin density wave (d-SDW) order and another associated with glassy weak magnetism (WM), are observed below ~100 K by muon spin rotation (muSR) in LaFeAsO1-xFx for x = 0.057(3) which is near the boundary of these phases on the doping phase diagram. In contrast to the competing order observed in the regular SDW phase of Ba(Fe1-xCox)2As2, the WM domain exhibits cooperative coupling of superconducting and magnetic order parameters as inferred from strong diamagnetism and associated negative shift of muSR frequency just below Tc.

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M. Hiraishi, R. Kadono, M. Miyazaki, I. Yamauchi, A. Koda, K. M. Kojima, M. Ishikado, S. Wakimoto, S. Shamoto. 2014-01-30. Cooperative order in the weakly magnetic domain of LaFeAsO$_{1-x}$F$_{x}$ near the doping phase boundary. https://doi.org/10.7566/jpsj.83.103707

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