DIFFERENTIAL RESISTANCE AND CRITICAL-CURRENT DISTRIBUTION IN AN AG-CLAD (BIPB)2SR2CA2CU3O10+Y TAPE

V-I characteristics of well characterised Ag-clad BPSCCO tape have bee n studied in the temperature (T) range 80-106 K and magnetic fields (B ) up to 60 mT. The zero field critical current density at 77 K was abo ut 10000 A cm-2. The variations of J(c) with B (B-0.5) and T [(1 - T/T (c))1.3] probably arise from the intragranular flux creep. The magnitu de and the variation of the differential resistance (R(f)) of BPSCCO c ore with T are consistent with those arising from the flux flow in low B. Very wide distribution of critical currents (CCD) within the core is tentatively ascribed to a broad distribution of the flux pinning en ergies in BSCCO.