Scanning Hall probe microscopy of flux penetration into a superconducting YBa2Cu3O7-delta thin film strip

A high-resolution scanning Hall probe microscope has been used to measure f lux profiles across one "wire" of a long YBa2Cu3O7-delta thin-film meander line as a function of both transport current density and applied magnetic f ield. Flux bundle penetration due to an applied current or magnetic field i s demonstrated to occur at the same regions at the edge of the strip. A cor relation between the surface topography of the meander line edges and the r egions of penetration has been established. Penetrating flux profiles at lo w temperatures are in qualitative agreement with theories of dynamical inst ability of the order parameter. (C) 2001 American Institute of Physics.