Growth and superconducting properties of Bi2Sr2CaCu2O8+delta single-crystal whiskers using tellurium-doped precursors

Bi2Sr2CaCu2O8+delta (Bi2212) single-crystal whiskers were grown by annealin g sintered Te-doped Bi-Sr-Ca-Cu-O precursors that had not passed through a melt-quenched glassy state, a process that is known well at this time. The optimum nominal composition of precursors is Ca-rich Bi2Sr2Ca2Cu2Te0.5Ox wi th a Te content of 0.5. The whiskers contain no Te element. The precursors are mainly composed of Bi2212 and (SrCa)(3)TeO6 (STO) phases. The STO or th e element Te acts as a catalyst in enhancing whisker growth. The critical c urrent (Ic) with a multibranched structure of the current-voltage character istics due to the intrinsic Josephson junctions along the c axis is quite u niform, showing that the whiskers are homogeneous and of good quality. (C) 2001 American Institute of Physics.