Large Bi-2212 single crystal growth by the floating-zone technique

Effects of growth velocity on the crystal-growth behavior of Bi2Sr2Ca1Cu2Ox (Bi-2212) have been studied by the floating-zone technique. The results show that a necessary condition for obtaining large single crystals along the c-axis is that the solid-liquid interface of a growing rod maintains a stable planar growth front. The planar liquid-solid growth interface tends to break down into a cellular interface when the growth velocity is higher than 0.25 mm/h. Single crystals of up to 50 x 7.2 x 7 mm 3 along the a-, b- and c-axes, respectively, have been cut from a 7.2 turn diameter rod obtained with optimum growth conditions. T-n(onset) is 91 K as determined from magnetization measurements on as-grown crystals. Optical polarization microscopy and neutron diffraction show that the quality of the large single crystals is good. Published by Elsevier B.V.