TY - JOUR
T1 - Proper composition for superconductivity in Pb(Ba, Sr)2(Y, Ca)Cu3O7
AU - Tokiwa, Ayako
AU - Nagoshi, Masayasu
AU - Syono, Yasuhiko
N1 - Funding Information:
The authors thank Drs. Y. Koike and M. Kikuchi for useful discussion, and Mr. Shioga, KKS Corporation for the composition analysis by SEM-EDX. Their thanks are also due to Prof. Y. Muto and Prof. M. Tachiki for warm encouragementt hroughout the study. This work was partly supported by a Grant-in-Aid for Scientific Research on Priority Area “Mechanism of Superconductivity” given by the Ministry of Education, Culture and Science, Japan.
PY - 1990/10/1
Y1 - 1990/10/1
N2 - Superconductivity and composition analysis of PbBaSr(Y, Ca)Cu3Oy with fixed ratio of Sr/Ba = 1 were studied. Synthesis condition and superconductivity of Pb(Ba, Sr)2(Y, Ca)Cu3Oy with various ratio of Sr/Ba and Ca/Y were also studied. It was found that Tc increased with increasing Ca concentration, and that Sr-rich specimens allowed to contain more Ca. PbBa0.8Sr1.2Y0.6Ca0.4Cu3O7 showed superconductivity with zero-resistance temperature of 42 K, which was higher than PbBaSrY0.7Ca0.3Cu3O7 with maximum Ca content for Sr/Ba = 1. Decrease in averaged ionic radii of Ba and Sr in Sr-rich compositions would be favorable for the contraction of Cu-O bonds by hole-doping via Ca substitution for Y.
AB - Superconductivity and composition analysis of PbBaSr(Y, Ca)Cu3Oy with fixed ratio of Sr/Ba = 1 were studied. Synthesis condition and superconductivity of Pb(Ba, Sr)2(Y, Ca)Cu3Oy with various ratio of Sr/Ba and Ca/Y were also studied. It was found that Tc increased with increasing Ca concentration, and that Sr-rich specimens allowed to contain more Ca. PbBa0.8Sr1.2Y0.6Ca0.4Cu3O7 showed superconductivity with zero-resistance temperature of 42 K, which was higher than PbBaSrY0.7Ca0.3Cu3O7 with maximum Ca content for Sr/Ba = 1. Decrease in averaged ionic radii of Ba and Sr in Sr-rich compositions would be favorable for the contraction of Cu-O bonds by hole-doping via Ca substitution for Y.
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U2 - 10.1016/0921-4534(90)90013-5
DO - 10.1016/0921-4534(90)90013-5
M3 - Article
AN - SCOPUS:0025508755
SN - 0921-4534
VL - 170
SP - 437
EP - 442
JO - Physica C: Superconductivity and its applications
JF - Physica C: Superconductivity and its applications
IS - 5-6
ER -