Al替代含量对YBa_2Cu_3O_y体系局域电子密度和超导电特性的影响  

EFFECT OF Al SUBSTITUTION DEPENDENCE ON ELECTRONIC STRUCTURE AND SUPERCONDUCTIVITY IN YBa 2Cu 3O y SYSTEMS

作　　者：魏淑桃[1] 康春雷[1] 尚家香 曹世勋 刘峰奇 张金仓 

机构地区：[1]河南师范大学

出　　处：《低温物理学报》1998年第4期316-320,共5页Low Temperature Physical Letters

摘　　要：研究了Ａｌ作铜位元素替代时ＹＢａ２Ｃｕ３Ｏｙ体系局域电子密度的变化，发现了存在于正交四方相变区域附近的异常特征，利用电子弱局域化理论对实验结果给予了初步解释，讨论了这种电子弱局域化效应对超导电特性的影响．Abstract We present the results of Al substituted in high T c cuprate perovskite YBa 2Cu 3O y systems. The local electron density n e was calculateds as a function of Al substitution x and a significant Al substitution dependence of the local electronic structure were observed. The results show that at low doping concertration, x ≤0.15, n e exists a large change and then reaches to a limit value of saturation or a peak value above x =0.15 which correspond just right to the known structural transition from orthorhombic to tetragonal phase. Here, the decrease in n e can be interprated by electronic weak localization in Cu O chains. The effect of n e on superconductivity was also discussed.

关 键 词：局域电子密度 超导体 YBCO体系 超导电性 

分 类 号：TM262.014[一般工业技术—材料科学与工程] O511[电气工程—电工理论与新技术]