Jc distribution measurement and analysis on superconducting bulk using 'Magnetoscan' method

We investigated experimentally and theoretically by the 'Magnetoscan' technique. The Hall probe should be scanned as near as possible on the surface. The scan of the permanent magnet causes the field trap on the bulk. The field trap seriously influences the magnetoscan signal detected by Hall probe. We have investigated the detection of the crystal defects and/or inhomogeneity of critical current density (Jc) in superconducting bulk experimentally and theoretically by the 'Magnetoscan' technique. To detect them sensitively, the Hall probe located near the permanent magnet should be scanned as near as possible on the surface of the superconducting bulk. The scan of the permanent magnet causes the field trap on the bulk, which seriously influences the magnetoscan signal detected by Hall probe.