Preparation of long Bi-2212 whiskers and their superconducting properties

The effects of oxygen gas flow rate on the growth of Bi2Sr2CaCu2Ox (Bi-2212) superconducting whiskers have been studied. Increasing the gas flow rate inhibits whisker growth and reduces both maximum and average whisker lengths. Flow rate should be kept as low as possible to obtain a long whisker. Apart from the top part, chemical composition and Tc are uniform in a whisker of 14 mm length. It is confirmed that the superconductivity of whiskers is not suppressed during growth of long duration.