Growth and Superconductivity of (BiPb)2Sr2Ca2Cu3O10+δ Single-Crystal Whiskers

(BiPb) 2 Sr 2 Ca 2 Cu 3 O 10+δ ((BiPb)2223) single-crystal whiskers with a length of about 2 mm were grown by annealing a sintered Te-doped (BiPb) 2 Sr 2 Ca 2 Cu 3 O x precursor pellet. The pellet was formed by mixing single-phase (BiPb)2223 with TeO 2 ; the content ratio of TeO 2 to Bi2223 was 0.5. For the growth, it is very important to use (BiPb)2223 single-phase powder as a precursor. The whiskers contain no Te and their composition is Ca-rich (BiPb) 2 (Sr 0.3 Ca 0.7 ) 4 Cu 3 O x . The whiskers have excellent crystallinity and a critical temperature of about 106 K. The critical current, which exhibits a multibranched structure in the current–voltage characteristics due to the intrinsic Josephson junctions along the c -axis, is quite uniform, showing that the whiskers are homogeneous and of good quality.