Effect of a cerium/tin doping mixture on the texturing process and on the superconducting properties of top seeded melt textured YBaCuO

• Published in: Journal of materials science Vol. 35; no. 21; pp. 5407 - 5413
• Main Authors: LEBLOND-HARNOIS, C, MONOT, I, DESGARDIN, G
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.2000; Springer Nature B.V
• Subjects: Cerium; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Copper; Critical current density; Critical temperature; Domains; Doping; Effects of material synthesis, crystal structure, and chemical composition; Exact sciences and technology; Granular, melt-textured, amorphous and composite superconductors; Inclusions; Inhomogeneous superconductors and superconducting systems; Materials science; Morphology; Physics; Superconductivity; Texturing; Tin; Transition temperature variations; YBCO superconductors; Critical current density; Inorganic compounds; Growth rate; Transition element compounds; Doping; Magnetic field effects; Crystal seeds; Experimental study; Inclusions; Fabrication property relation; Texture; Submicron particle; Tin additions; Barium oxides; High-Tc superconductors; Cerium additions; SEM; Microstructure; Quaternary compounds; Copper oxides; Inhomogeneous materials; Superconducting transition; Yttrium oxides; Melts
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1023/A:1004811315866

The influence of a cerium/tin doping mixture on top seeded melt textured pellets of YBa2Cu3O7−δ/Y2BaCuO5 (Y123/Y211) was investigated and compared with cerium doping. The thermal cycle of the texturing process has been adapted to this new composition, considering the variations of the decomposition temperature and of the melt viscosity. Growth rates of YBCO crystals appear to be quadrupled by the presence of tin. We manage to grow domains of diameter 30 mm from a SmBa2Cu3O6+δ seed. SEM observations have shown no modification of the Y2BaCuO5 inclusions either in size or in morphology compared to Y211 particules in cerium doped YBCO. However, EDS analyses have revealed the existence of submicron particles containing Y, Ba, Cu, Sn, Ce and O distributed in the matrix. Superconducting properties are greatly improved by the addition of a moderate amount of tin to the cerium doped YBCO. The critical temperature is shifted toward 92 K with a transition width of 0.5 K. Critical current densities at 77 K reach values as high as 9 × 104 A/cm2 in self field, 5 × 104 A/cm2 under 1 Tesla and still 2.5 × 104 A/cm2 under 2 T, which are among the best results ever obtained for top seeded doped YBCO.