COMPOSITION AND STRUCTURE REFINEMENT OF SUPERCONDUCTING CRYSTALS Y1-xTbxBa2Cu3O6+Оґ (х = 0.10; Оґ = 0.75)
L. P. Kozeeva, N. V. Podberezskaya, N. V. Kuratieva, M. Y. Kamaneva, A.G. Blinov
Keywords: superconducting crystals Ln123, (Y/Tb)123 crystals, crystallization, structure, solid solutions, superconductivity
Pages: 1101-1107
Abstract
Crystals of Y0.90Tb0.10Ba2Cu3O6.75 have been prepared by spontaneous crystallization from slowly cooled non-stoichiometric melt of the system Y-Tb-Ba-Cu-O. Average size of platelet crystals having mirror surface is 2×2, the largest - 8×9 mm with thickness 0.1-0.2 mm. The crystals have been characterized by powder X-ray diffraction and electron microprobe analysis. Tetragonal symmetry of the crystals has been determined by X-ray diffraction. Magnetic susceptibility measurements have revealed that the crystals manifest transition to superconducting state without additional annealing (Тс = 60 K). Structures and compositions - Y/Tb ratio (σ = 0.01) and oxygen content (σ = 0.04) - have been refined for two single crystals. Possibility of rhombic distortion of the tetragonal symmetry is discussed.
|
