ANGULAR-DEPENDENCE OF ISOTHERMAL REMANENT MAGNETIZATION OF SPUTTERED YBCO THIN-FILMS

Because of their intrinsic layered structure, high temperature superco nductors are suitable systems for studying the strong anisotropy of th eir superconducting properties. In fact, the response of a sample to a n external magnetic field H depends generally not only on the magnitud e but also on the orientation of H. Since remanent magnetization is a measurement of the effective flux-pinning strength in superconductors, it depends upon both the temperature and the applied field, as well a s on the history of processing and the angle between the applied magne tic field and the crystallographic axis directions. In this framework we report the studies of the angular dependence of remanent isothermal magnetization M-rem in YBCO sputtered films. The projections of the r emanent magnetization on the direction of the magnetometer axis were m easured for each of the films. The results show the orientational pref erence for flux trapping, related to intrinsic features. Moreover, an angular dependence of the remanent magnetization can be calculated in good agreement with the experimental data.