Temperature-dependent and magnetic-field-dependent measurements of the microwave surface impedance of superconducting LaFeAsO0.9F0.1 (Tc≈26 K) reveal a very large upper critical field (Bc2≈56 T) and a large value of the depinning frequency (f0≈6 GHz); together with an upper limit for the effective London penetration depth, λeff≤200 nm, our results indicate a strong similarity between this system and the high-Tc superconducting cuprates.
Narduzzo, A., Grbić, M., Požek, M., Dulčić, A., Paar, D., Kondrat, A., Hess, C., Hellmann, I., Klingeler, R., Werner, J., Köhler, A., Behr, G., & Büchner, B. (2008). Upper critical field, penetration depth, and depinning frequency of the high-temperature superconductor LaFeAsO0.9F0.1 studied by microwave surface impedance. Physical Review B, 78(1), . https://doi.org/10.1103/PhysRevB.78.012507