Bi2Sr2CaCu2Oy single crystal growth in Bridgman-Stockbarger method using different oxygen partial pressure

In order to attain the application of Bi2Sr2Can-1Cun-1Oy (Bi-based) high-T-c superconductor to terahertz electronic devices which work in a wider radio-frequency region, it is required to obtain large and high quality Bi-based superconducting single crystals. For obtaining large and high quality single crystals, it is necessary to clarify the effects of oxygen partial pressure of a crystal growth atmosphere (P-O2) on the grown single crystals as it is known that the control of the P-O2 is effective to enhance the size of single crystals and to control their superconducting properties. In this study, we prepared Bi2Sr2CaCu2Oy (Bi-2212) superconducting single crystals by a modified Bridgman-Stockbarger method, i.e. a modified vertical Bridgman (VB) method, using various P-O2 and characterized their sizes and superconducting properties to clarify the effect of the P-O2 on the grown single crystals. From the results, we found that we could obtain large single crystal with the size of 133.3 mm(2) (=20.5 mm x 6.5 mm) in ab-plane at the P-O2 of 21 kPa. The superconducting critical temperature (T-c) and the full width at half maximum (FWHM) value of the (00 (1) under bar(0) under bar) X-ray diffraction peak from a Bi-2212 superconductor of the grown single crystal were 88 K and 0.05 degrees, respectively. (c) 2006 Elsevier B.V. All rights reserved.