Upper critical field, penetration depth, and depinning frequency of the high-temperature superconductor LaFeAsO0.9F0.1 studied by microwave surface impedance

Temperature-dependent and magnetic-field-dependent measurements of the microwave surface impedance of superconducting LaFeAsO(0.9)F(0.1) (T(c)approximate to 26 K) reveal a very large upper critical field (B(c2)approximate to 56 T) and a large value of the depinning frequency (f(0)approximate to 6 GHz); together with an upper limit for the effective London penetration depth, lambda(eff)<= 200 nm, our results indicate a strong similarity between this system and the high-T(c) superconducting cuprates.