We report Ca-site selectivity in the crystal structure of Y124(YBazCu4O8) superconductor. We sucsessfiilly synthesized superconducting samples with nominal compositions of (Y1-xCax)Ba2Cu6O8 (series-A: x=0.0, 0.05, 0.1) and Y(Ba2-yCay)Cu4O8) (series-B: y=0.0, 0.05, 0.1) by polymerized complex method followed by O2-IIIP technique. Neutron powder diffraction measurement has shown excess impurities in propotion to Ca-content in series-B. An extension of A Tc(10-90%) was also observed in series-B by AC-magnetic susceptibility measurement It is suggested that the formation of these impurities in series-B originate from a discrepancy in idea] composion, that is, (Y1-xCax)Ba2Cu4O8 (seires-A). We conclude that Ca-atom preferentially substitutes Y-atom in the 124 structure for these reasons.
|ジャーナル||journal of the japan society of powder and powder metallurgy|
|出版ステータス||Published - 1994 2 1|
ASJC Scopus subject areas