Superconducting whiskers and crystals of the high T c Bi2Sr2Ca2Cu3O10 phase

Whiskers of the high Tc Bi2Sr2Ca2Cu3O10 (2223) phase have been prepared by annealing Bi2Sr2CaCu2O8 (2212) whiskers in a Bi2Sr2Ca4Cu6Pb0. 5Ox powder. By the same method, single-crystal sheets of the 2212 phase have also been converted to the 2223 phase, resulting in 2223 sheet crystals as large as approximately 1 mm2. Although the original sample outlines are retained after the phase conversion, the smooth surfaces were lost due to contact with the powder during annealing. A zero-resistance temperature of 107 K and a maximum Jc value of 7.3×104 A/cm2 at 77 K in a zero magnetic field were obtained for the 2223 whisker.