N ov 1 99 8 Microwave surface impedance of proximity - coupled superconducting ( Nb ) / spin - glass ( CuMn ) bilayers
نویسندگان
چکیده
The surface impedance of Nb/CuMn (superconducting/spin-glass) bilayers has been measured at 10 GHz with the parallel plate resonator technique to obtain information about the exotic behavior of the order parameter in superconducting/magnetic proximity systems. The data strongly differs from the superconducting/normal-metal case, showing the magnetic nature of the CuMn layer, which acts as a weak ferromagnet. The results are described in the framework of two models for the electrodynamics of superconducting/ferromagnetic (S/M) bilayers characterized by a proximity-coupling length scale which is independent of temperature. PACS: 74.80.Dm, 74.50.+r, 74.25.Nf. Typeset using REVTEX ∗On leave from Dipartimento di Fisica, Università degli Studi di Salerno, Baronissi, Salerno I84081, Italy.
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