Analysis of the magneto-transport properties of superconducting/ferromagnetic YBa2Cu3O7/La0.7Sr0.3MnO3 bilayer thin films

Y1Ba2Cu3O7−δ (100 nm)/La0.7Sr0.3MnO3 (20 nm) double-layered films and La0.7Sr0.3MnO3 (20 nm) single layer films were prepared on LaAlO3 substrates by magnetron sputtering and their electrical and magnetic properties were examined. It was observed that the interactions between magnetic and superconducting layers lead to some peculiar electrical and magnetic properties such as a semiconducting-like behavior above superconducting transition temperature. Possible reasons of this behavior and others are discussed in the text. Additionally, it is observed that the SC/FM film has a quite low coercivity (50 Oe) and large Mr/Ms ratio (0.8) at 300 K. The extraordinary properties of these materials may give rise to their utilization of these films for temporary recording of information on magnetic surfaces.