YBa_2Cu_3O_(7-δ)外延薄膜的有效钉扎势  

EFFECTIVE PINNING POTENTIAL IN EPITAXIAL YBa_2Cu_3O_[7-δ] THIN FILM

作　　者：王智河[1] 曹效文[2] 陈敬林[2] 李可斌 

机构地区：[1]中国科学院上海冶金研究所 [2]中国科学院等离子体物理研究所 [3]中国科学院固体物理研究所

出　　处：《物理学报》1998年第10期1720-1726,共7页Acta Physica Sinica

摘　　要：在０—７Ｔ磁场范围内，测量了不同测量电流密度下ＹＢａ２Ｃｕ３Ｏ７－δ外延薄膜的电阻温度关系．实验结果表明，临界温度以下，混合态的耗散电阻率能很好地用热激活磁通蠕动描述．有效钉扎势的电流密度关系遵守Ｚｅｌｄｏｖ等人提出的对数关系，有效钉扎势的温度和磁场关系遵守Ｕ∝（１－Ｔ／Ｔｃ）Ｈ－α关系，其中α＝０６３，与热激活磁通点阵位错运动模型相一致，表明样品具有２Ｄ涡旋性质．AbstractThe temperature dependence of the resistivity of an epitaxial YBa_ 2Cu_3O_[7-δ] thin film has been measured in various magnetic fields up to 7T applied parallel to the c axis near Tc. The result shows that the resistivity below T c can be well fitted by thermally activation flux motion. The current density dependence of the effective pinning potential follows a logarithmic law proposed by Zeldov et al. The temperature and magnetic field dependence of the effective pinning potential follows U(H,T)=U 0(1-T/T c)H-α, with α=063, showing 2D behavior, It is consistent with the plastic deformation model of the flux line lattice at flux line lattice dislocations.

关 键 词：高TC 超导体 有效钉扎势 YBCO 外延 薄膜 

分 类 号：TM262[一般工业技术—材料科学与工程]