arXiv 0806.14432008-06cond-mat.supr-concond-mat.str-el

Upper critical field, penetration depth, and depinning frequency of the novel high-temperature superconductor LaFeAsO$_{0.9}$F$_{0.1}$ studied by microwave surface impedance

A. Narduzzo, M. S. Grbić, M. Požek, A. Dulčić, D. Paar, A. Kondrat, C. Hess, I. Hellmann, R. Klingeler, J. Werner, A. Köhler, G. Behr, B. Büchner

备注：: 4 pages, 6 figures, minor corrections and rephrasing
发表信息：: Physical Review B, 78, 012507 (2008)
DOI：: 10.1103/PhysRevB.78.012507

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Temperature and magnetic field dependent measurements of the microwave surface impedance of superconducting LaFeAsO$_{0.9}$F$_{0.1}$ (\Tc $\approx$ 26K) reveal a very large upper critical field ($B_{\rm c2} \approx 56$T) and a large value of the depinning frequency ($f_{0}\approx 6$GHz); together with an upper limit for the effective London penetration depth, $λ_{\rm eff} \le 200 \rm nm$, our results indicate a strong similarity between this system and the high-$T_{\rm c}$ superconducting cuprates.

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