Low-field AC susceptibility study of the flux motion in Bi2Sr2CaCu2Oy thin films

DC magnetron sputtering technique were used for the synthesis of high quality epitaxial thin films of the superconducting cuprate Bi(2)Sr(2)CaCu(2)Oy (Bi: 2212) thin films. The structural characterization carried by X-ray diffraction indicates that the films are single phase and oriented with their c-axis perpendicular to the substrate surface. The flux motion mechanisms in the vicinity of the irreversibility line have been studied by AC susceptibility technique. The temperature dependencies of real and imaginary parts of AC susceptibility were performed, by using different values of amplitude and frequency. Temperature dependence and low field dependence of the activation energy for flux motion were obtained