新块材超导体Pr_(1-x)Ca_xBa_2Cu_3O_(7-δ)(0.4≤x≤0.6)的高压合成与超导电性  

HIGH PRESSURE SYNTHESIS AND SUPERCONDUCTIVITY OF NEW BULK Pr_[1-x]Ca_xBa_2Cu_3O_[7-δ]SUPERCONDUCTORS

作　　者：熊玉峰[1] 金铎[1] 姚玉书[2] 吴非[2] 贾顺莲[2] 赵忠贤[2] 

机构地区：[1]中国科学院低温技术实验中心 [2]中国科学院物理研究所超导国家重点实验室

出　　处：《物理学报》1998年第10期1713-1719,共7页Acta Physica Sinica

摘　　要：采用高温高压合成方法，合成出了Ｐｒ１－ｘＣａｘＢａ２Ｃｕ３Ｏ７－δ（０４≤ｘ≤０６）系列块材超导体，在缺氧的Ｐｒ０．５Ｃａ０．５Ｂａ２Ｃｕ３Ｏ７－δ四方１２３结构样品中得到了Ｔｃ为９８Ｋ．实验结果表明Ｐｒ在１２３结构中的价态为大于３＋的混合价态，因而空穴填充和杂化导致的载流子局域化是Ｐｒ抑制１２３相超导电性的关键因素．AbstractThe new bulk superconductors of Pr_[1-x]Ca_xBa_2Cu_3O_[1-δ] (0.4≤x≤0.6) have been synthesized under high pressure for the first time to our knowledge. The highest Tc of 98K was observed for Oxygen deficient tetragonal Pr_0.5Ca_0.5Ba_2Cu_3O_[7-δ] sample. Our results demonstrate the valence state of Pr in 123 structure is a mixed sate greater than 3+, hole filling and hybridization are the primary cause of the suppression of superconductivity by Pr in 123 structure.

关 键 词：超导电性 高压合成 超导体 块材 PCBCO 

分 类 号：TM262.05[一般工业技术—材料科学与工程] TM262.014[电气工程—电工理论与新技术]