Abstract
Bulk samples with nominal composition of Bi2Sr2CaCu2Oy doped with 0, 10 and 20 weight % Ag were prepared by the floating-zone method at growth rates of 2 mm/h and 5 mm/h. Ag-doping seems to slightly enhance Jc, while annealing is very effective for Jc enhancement. From preliminary ac susceptibility measurements, the Jc enhancement by annealing is considered to be due to improvement of the weak link between superconducting grains. The 10% Ag-doped sample grown at 2 mm/h possessed Jc of 5360 A/cm2 at 77 K under zero magnetic field after annealing.