Local critical current measurements on (Bi,Pb)2Sr2Ca2Cu3Ox tape with an electromagnetic probe

The ability to measure critical currents in high Tc superconducting tapes on a local scale is valuable for optimizing the fabrication process. This paper describes the use of induced currents from a small noncontacting electromagnetic probe to determine the critical current density in a (Bi,Pb)2Sr2Ca2Cu3Ox/Ag tape on a local scale. The technique forces full field penetration into the tape locally and infers the critical current density from the Bean critical state model, accounting for the Ag overlayers. Critical current images of the till can be obtained by scanning the probe over the tape surface with spatial resolution on the order of 1.0 mm. Results for tapes with different microstructures we discussed