Growth and physical properties of Bi2Sr2CaCu2O8+x crystals grown by a simple pressure technique and comparison with regrowth self-flux technique

Single crystals of a high temperature superconductor Bi2Sr2CaCu2O8+x (2212) were grown using two different techniques, namely, regrowth technique as well as a pressure technique and the results are compared. Single crystal X-ray diffraction (XRD) performed on crystals grown using both techniques show no impurity or intergrowth phase. However, powder XRD reveals the presence of only Bi2Sr2CuO6+x(2201) intergrowth phase in crystals grown using pressure technique, with additional impurity phases also found in the crystals grown using regrowth technique. Rietveld refinement showed the weight fraction of 2212 as 93% in crystals grown from pressure technique, confirming the excellent quality of the as-grown crystals. The transition temperature of crystals grown using both techniques was ∼90 K. It was found that pressure technique gives crystals that have a higher superconducting volume fraction (∼100) than that of crystals grown using regrowth technique. Structural and magnetization measurements reveal that the as-grown crystals grown using pressure technique are of high quality, comparable to those grown using traveling solvent floating zone technique. Crystals grown by both the techniques exhibit second magnetization peak anomaly.