Dependence of the magnetization in YBa2Cu3O7−x thin films on the applied magnetic field direction

The dependence of the magnetization on the applied magnetic field direction was investigated at 5 K on superconducting thin films of YBa2Cu3O7−x prepared by ArF laser ablation with the c axis perpendicular to the film plane. The difference of the magnetic moment between the increasing and decreasing branches of the hysteresis curves at zero field depends on the angle θ between the film normal and the magnetic field as ‖cos θ‖. This result can be attributed to the magnetic moment perpendicular to the film plane.