题名 |
The Search for Novel High Temperature Superconductors: The Ba-Ca-Cu-0 System |
作者 |
C. W. Chu;Z. L. Du;Y. Y. Xue;Y. Cao;N. L. Wu;Y. Y. Sun;I. Rusakova |
关键词 | |
期刊名称 |
Chinese Journal of Physics |
卷期/出版年月 |
36卷2S期(1998 / 04 / 01) |
页次 |
139 - 148 |
内容语文 |
英文 |
英文摘要 |
Following the recently observed empirical rule, two new high-temperature superconducting homologous series of the Ba-Ca-Cu-0 system have been discovered by using the high pressure synthesis technique: the interstitially doped Ba2Can-1CunO2n+2[02(n-1) n] for n = 3 and 4, and the CaBa2Can-1CunO2n+3[Ca-12(n-1) n] for n = 3. The 14-symmetric 02(n-1)n shows a Tc up to 126 K, the highest for superconductors without any volatile toxie elements, and degrades to a lower Tc compound when exposed to air; whereas the P4-symmetric Ca-12(n-1)n displays a Tc not to exceed 107 K and remains stable in air. More superconducting phases with a Tc up to 120 K have been detected in the Ba-Ca-G-0 system, although their structures have yet to be determined. These cornpounds provide excellent opportunities for the study of the role of charge-reservoir in high-temperature superconductivity, and the effects of symmetry on T, and structural instability. They may also be good material candidates for high-temperature superconducting thin-film devices operable above 120 K. |
主题分类 |
基礎與應用科學 >
物理 |
被引用次数 |