A Pinning Mechanism of YBaCuO Thin Film Dispersed with Differently-Oriented Crystal Grains

On the surface of YBaCuO thin film grown on LaAlO3 substrate using laser deposition method with Jc value of about 1×106 A/cm2,had many crystal grains of about l μm ×0.lμm. These crystal grains had the same crystal structure as the matrix, but had different crystal axis. The magnetization at 77 K had a small peak when the magnetic field were applied at an angle of 30° from c-axis of the matrix, which miay be explained by the flux pinning by the boundaries between the crystal grains and the matrix..