Stoichiometry and Superconductivity in Single Layer Bi2+Xsr2-YCuO6+-Δ
Document Type
Article
Publication Date
1-15-1991
Journal / Book Title
Physica C: Superconductivity
Abstract
An insulating polymorph with a composition close to Bi2Sr2CuO6 complicates the synthesis of the single copper layer superconductor Bi2+xSr2-yCuO6±δ. We concentrate on the region where the material is single phase in air synthesis (2.18 < x < 2.29, 1.44 < y < 1.7). The physical properties from insulating to marginally conducting as the composition moves toward x = y = 0. Like to two-layer compound, the material has a superlattice due to a buckling of the planar structure, however the superlattice coherence is degraded by defects at finite values of x and y. Density measurements indicate that the nonstoichiometry of Bi2+xSr2-y CuO6±δ is not accompanied by the formation of a large number of vacancies. The insulating polymorph, Bi2Sr2CuO6, can be suppressed by synthesis in modest oxygen pressures (above 5-10 atm). The result is a bulk superconductor (Tc ≈ 10 K).
DOI
10.1016/0921-4534(91)90791-V
Montclair State University Digital Commons Citation
Fleming, R. M.; Sunshine, Steven A.; Schneemeyer, Lynn; Van Dover, Robert B.; Cava, Robert J.; Marsh, P. M.; Waszczak, Joseph V.; Glarum, Sivert H.; Zahurak, S. M.; and Di Salvo, Francis J., "Stoichiometry and Superconductivity in Single Layer Bi2+Xsr2-YCuO6+-Δ" (1991). Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works. 72.
https://digitalcommons.montclair.edu/chem-biochem-facpubs/72
