High-temperature Superconductivity In Yttrium Barium Copper Oxide (YBa2Cu3O7) And Related Perovskite Oxides: Some Aspects Of Solid State Chemistry

Content Provider	Indian Institute of Science (IISc)
Author	Rao, C. N. R. Ganguly, P. Sreedhar, K. Ram, Mohan Ra Sarode, P. R.
Copyright Year	1987
Abstract	Thermogravimetry and Cu "K-absorption edge measurements show that the superconducting $YBa_2Cu_30_7$ sample (annealed in $0_2$) contains more oxygen than the nonsupe conducting sample annealed in-$N_2$, the former has s less distorted structure with the actual composition not far from the ideal one. Oxides of the formula $Y_{l-x} Ba_2Cu_30_7$ (x = 0.05, 0.10 and 0.15) annealed in oxygen also possess the perovskite structure and show high-$T_c$ superconductivity. The superconduccting transition temperature seems to generally increase with the nominal $Cu^{3+} Cu^{2+}$ ratio in the superconducting copper oxides. Control of the $Cu^{3+} Cu^{2+}$ ratio (and hence the density of states at the metal-nonmetal transition in the non-superconducting state) through the oxygen stoichiometry or an appropriate cation substitution seems to provide a basis for synthesizing high-$T_c$ copper oxides.
File Format	PDF
Journal	PeerReviewed
Language	English
Publisher	Elsevier Science
Publisher Date	1987-01-01
Access Restriction	Authorized
Subject Keyword	Solid State & Structural Chemistry Unit
Content Type	Text
Resource Type	Article