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arXiv · 0803.0128

Superconducting properties of Fe-based layered superconductor LaO$_{0.9}$F$_{0.1-δ}$FeAs

G. F. Chen·Z. Li·G. Li·J. Zhou·D. Wu·J. Dong·W. Z. Hu·P. Zheng·Z. J. Chen·H. Q. Yuan·J. Singleton·J. L. Luo·N. L. Wang
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Abstract

We have employed a new route to synthesize single phase F-doped LaOFeAs compound and confirmed the superconductivity above 20 K in this Fe-based system. We show that the new superconductor has a rather high upper critical field of about 54 T. A clear signature of superconducting gap opening below T$_c$ was observed in the far-infrared reflectance spectra, with 2$Δ/\textit{k}T_c\approx$3.5-4.2. Furthermore, we show that the new superconductor has electron-type conducting carrier with a rather low carrier density.

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G. F. Chen, Z. Li, G. Li, J. Zhou, D. Wu, J. Dong, W. Z. Hu, P. Zheng, Z. J. Chen, H. Q. Yuan, J. Singleton, J. L. Luo, N. L. Wang. 2008-06-28. Superconducting properties of Fe-based layered superconductor LaO$_{0.9}$F$_{0.1-δ}$FeAs. https://doi.org/10.1103/physrevlett.101.057007

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