Lateral critical current distribution and self-field profile of Bi-2223/Ag conductors: measurements and calculations

The lateral current distribution and the magnetic self-field induced by a transport current were measured independently in three multifilament Bi-2223/Ag tapes with qualitatively different filament layouts. The current and field data from these two experiments, magnetic knife and scanning Hall probe, are compared with each other after straightforward 'forward' or 'inverse' current-to-field calculations. Both datasets show the critical current to be maximal in the central part of the tapes, while the comparison demonstrates that the drop of the critical current distribution at the tape edges is an intrinsic material property and is not caused by the tape's magnetic self-field. Small differences between the datasets reveal the effect of filament bridging.