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

doi:10.1103/physrevb.78.012507

arXiv · 0806.1443

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

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Abstract

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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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. 2008-10-07. 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. https://doi.org/10.1103/physrevb.78.012507

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