电子型超导体Pr_(1.85)Ce_(0.15)CuO_(4-δ)中Cu位V替代对超导电性的影响  

EFFECT OF V^(4+) SUBSTITUTION FOR Cu^(2+) IN ELECTRON-DOPED SUPERCONDUCTOR Pr_(1.85)Ce_(0.15)CuO_(4-δ)

作　　者：刘芬[1] 曹世勋[1] 黎文峰[1] 李领伟[1] 池长昀[1] 敬超[1] 张金仓[1] 

机构地区：[1]上海大学物理系,上海市上大路99号200444

出　　处：《低温物理学报》2005年第A01期432-438,共7页Low Temperature Physical Letters

基　　金：国家自然科学基金项目(批准号:10274049);上海市教育委员会曙光计划项目(批准号:03SG35);上海市教育委员会重点学科建设项目的资助~~

摘　　要：本文研究了Pr1.85Ce0.15CuO4-δ(PCCO)中V4+离子替代Cu2+离子后对其超导电性的影响.Pr1.85Ce0.15Cu1-xVxO4-δ(x=0~0.10)电阻率测量结果显示:微量(x≤0.04)V4+离子替代Cu2+离子可以改善样品的超导电性;随着替代量的增加,体系的超导电性逐渐被抑制,x=0.08时超导电性消失.我们主要从样品的微观结构和载流子浓度两个方面的变化分析了V4+替代Cu2+对PCCO超导电性的影响机制.霍尔系数实验结果表明,替代量较少时,体系中载流子浓度随着x的增加而增加,有助于超导电性的改善,但是当替代量增加到一定程度时,晶格畸变程度的增大和顶点氧的出现,抑制了超导电性.The effect of V^4＋ substitution for Cu^2＋ on superconductivity in electrondoped superconductor Pr1.85Ce0.15CuO4-δ has been studied. Results of resistivity of Pr1.85Ce0.15Cu1-xVxO4-δ（0≤x≤0. 10） proved： small amount substitution （x≤0. 04） of V^4＋ enhanced the superconductivity property; However with x increase, the superconductivity was suppressed gradually, as x=0. 08, superconductivity vanished. Then we discussed the effect of V^4＋ substitution for Cu^2＋ on the changes of microstructure and carrier concentration. Experiments of Hall coefficient showed that carrier concentration became increasing with little V^4＋ doped, which could help enhance the superconductivity property. But as x increased to some degree （for the sample x=0.06）, the aberrance of crystal lattice and the appearance of apical oxygen suppressed the samples＇ superconductivity.

关 键 词：电子型高温超导体 超导电性 微观结构 载流子浓度 

分 类 号：O511.2[理学—低温物理] X703[理学—物理]