Magneto-optical investigation on YBa2Cu3O7−x thin films on SrTiO3

The vortex motion when the external field penetrates perpendicularly square YBa2Cu3O7−x thin films deposited on misoriented SrTiO3 platelets has been pictured in situ by magneto-optical imaging. The visualized vortex pinning profile allows large-scale characterization of the superconducting quality of the thin film surface enabling tracing of areas of reduced superconducting properties or of various film defects. The obtained magneto-optical (M-O) images in combination with magnetization measurements can produce reliable estimations of the supercurrents flowing at each point of the film surface. The findings indicate a 40% anisotropy in the current distribution along the different [1 0 0] and [0 1 0] orientations for films deposited on substrates miscut at angles >1.69°.