Structure and superconducting properties of Ga-substituted YBa2Cu3O7–δand YBaSrCu3O7–δsystems

Autor:	C. N. Ramachandra Rao, Rajamani Nagarajan
Rok vydání:	1993
Předmět:	Superconductivity Chemistry business.industry Transition temperature Inorganic chemistry Yba2cu3o7 δ General Chemistry Magnetic susceptibility Crystallography Semiconductor Electrical resistivity and conductivity Materials Chemistry Cuprate business Chemical composition
Zdroj:	J. Mater. Chem.. 3:969-973
ISSN:	1364-5501 0959-9428
DOI:	10.1039/jm9930300969
Popis:	In YBa2Cu3–yGayO7–δ, Ga can be substituted at the Cu(1) site up to y= 0.1 without change in structure, but this is accompanied by a slight decrease in the hole concentration and Tc; the same is true when Y is partly substituted by Ca, as in Y1–xCaxBa2Cu3–yGayO7–δ(0.0 0.2. The y= 0.3 and 0.4 compositions show metal–semiconductor transitions at 60 and 120 K, respectively, while the y= 0.6 composition is a semiconductor. When Y is partly substituted by Ca as in Y1–xCaxBaSrCu3–yGayO7–δ, the material is superconducting even when y= 0.3. All these Ga-substituted cuprates are in the underdoped region and accordingly Tc increases with increase in hole concentration.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::ebdcc9a97aadd3cec7a6db782eb43f08 https://doi.org/10.1039/jm9930300969 Zobrazit plný text záznamu