Enhancement of Bi-2223 phase formation by electrical assisted laser floating zone technique

• Published in: The Journal of physics and chemistry of solids Vol. 67; no. 1; pp. 416 - 418
• Main Authors: Carrasco, M.F., Lopes, A.B., Silva, R.F., Vieira, J.M., Costa, F.M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 2006; Elsevier
• Subjects: A. Superconductors; Bi-based cuprates; C. Electron microscopy; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cuprates superconductors (high tc and insulating parent compounds); D. Microstructure; Exact sciences and technology; Physics; Superconductivity; D. Microstructure; C. Electron microscopy; A. Superconductors; Crystallization; Bismuth oxides; Interdiffusion; Floating zone; Texture; Heat treatments; Cuprates; Solidification; Calcium oxides; Strontium oxides; Laser radiation; High-Tc superconductors; Phase equilibria; Microstructure; Copper oxides; Crystal growth from melts
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2005.10.021

Application of the electrical assisted laser floating zone (EALFZ) technique to the growth of Bi–Sr–Ca–Cu–O superconducting fibres modifies the crystallization path during solidification. Under the electrical current, strong grain alignment in pull direction is obtained and the primary phase to crystallize is the equilibrium phase (Sr x Ca 1− x ) 14Cu 24O 41 (14/24) instead of the metastable Sr x Ca 1− x CuO 2 (1/1) cuprate that appears in the conventional LFZ process. Also, the superconducting phase development kinetics of EALFZ fibres during heat treatment differs from that of LFZ processed ones. An outstanding increase in the amount of the high critical temperature phase Bi 2Sr 2Ca 2Cu 3O 10 (2223) takes place as a result of interdiffusion across the interface between reactant phases 14/24 and Bi 2Sr 2CaCu 2O 8 (2212). The 2223 new crystals grow in bulk form in a perpendicular direction to the fibre axis.