Flux patterns of multifilamentary Ag-sheathed (Pb,Bi)(2)Sr2Ca2Cu3O10+deltatapes

Flux patterns of multifilamentary Ag-sheathed (Pb,Bi)(2)Sr2Ca2Cu3O10+delta tapes comprising 19 filaments are visualized by means of magneto-optic imag ing. In low fields, the shielding currents are seen to flow mainly in the o utermost filaments. With increasing external magnetic field, the inner fila ments also contribute to the current flow. To compare the local flux distri bution with the integral magnetization values, magnetization loops are meas ured by a SQUID magnetometer on the same sample following the fields used i n the magneto-optic imaging (+/-120 mT) and covering fields up to +/-5 T at various temperatures. The magnetization loops also reveal that the multifi lamentary tapes show the anomalous position of the central peak, but always less pronounced than in monofilamentary tapes. (C) 1998 American Institute of Physics.