Scanning Hall probe microscopy of flux penetration into a superconducting YBa[sub 2]Cu[sub 3]O[sub 7-δ] thin film strip.

A high-resolution scanning Hall probe microscope has been used to measure flux profiles across one "wire" of a long YBa[sub 2]Cu[sub 3]O[sub 7-δ] thin-film meander line as a function of both transport current density and applied magnetic field. Flux bundle penetration due to an applied current or magnetic field is demonstrated to occur at the same regions at the edge of the strip. A correlation between the surface topography of the meander line edges and the regions of penetration has been established. Penetrating flux profiles at low temperatures are in qualitative agreement with theories of dynamical instability of the order parameter. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]