Growth of High Quality Bi\(_2\)Sr\(_2\)CaCu\(_2\)O\(_{8+\delta }\) Single Crystals with a High Critical Temperature of 96 K Using Alumina Crucible

The growth of the high-T\(_c\) cuprate Bi\(_2\)Sr\(_2\)CaCu\(_2\)O\(_{8+\delta }\) (BSCCO-2212) superconductor is always challenging due to the contamination from alumina crucible or the intergrowth of other phases such as Bi\(_2\)Sr\(_2\)CuO\(_{6+ \delta }\) (Bi-2201). In this work, we report the synthesis of single crystals of BSCCO-2212 with the highest reported superconducting transition temperature, T\(_c\), of 96.6 K, achieved using an improved self-flux technique. The as-grown crystals were characterized by scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and powder x-ray diffraction (p-XRD) measurements. PXRD on single crystals reveals the absence of contamination from the alumina crucible as well as the absence of the intergrowth of Bi-2201 phase. PXRD on crushed single crystals reveals minimal intergrowth of Bi-2201 and Bi-2223 phases. The physical properties were investigated by carrying out temperature-dependent magnetization and resistance measurements. Magnetization measurements revealed the T\(_c\) of three single crystals of BSCCO-2212 to be 93 K, 94 K, and 96.6 K, higher than the previously reported values in the range from \(\sim \) 90 to 93 K [1,2,3,4,5]. Such a high T\(_c\) and the absence of an intergrowth phase indicates a good quality of the grown crystals that can be utilized for fundamental as well as basic research.