熔融织构YBCO单晶的层间耦合  

COUPLING BETWEEN LAYERS IN MTG YBCO SINGLE CRYSTALS

作　　者：王智河[1] 胡永祥[1] 张宏[1] 方军[2] 王胜[2] 陈敬林[2] 高秉均 曹效文[2] 

机构地区：[1]中国科学院上海冶金研究所,上海200050 [2]中国科学院等离子体物理研究所,合肥230031

出　　处：《低温物理学报》1999年第6期460-463,共4页Low Temperature Physical Letters

基　　金：国家超导中心资助

摘　　要：在０ ～７．５Ｔ磁场范围内，采用膺磁通变压器结构（ 八电极） ， 测量了磁场平行于ｃ 轴时熔融织构生长的ＹＢＣＯ单晶上和下两个表面的电阻温度关系．实验结果表明， 在测量仪表所能测量的精度范围内， 没有观测到Ｖｔｏｐ 等于Ｖｂｏｔ 的情况，Ｖｔｏｐ 总是大于Ｖｂｏｔ．不同磁场下Ｖｔｏｐ／Ｖｂｏｔ随着温度的降低而变化；ｃ轴电阻的测量结果则表明， 样品沿ｃ 方向与ａｂ 面具有相似的超导电性， 且Ｔｃｃ ＞ Ｔａｂｃ ， 这充分表明随着温度的降低， 层间耦合增强，在更低温度下具有３ Ｄ 特征．We have measured the temperature dependence of resistivity on MTG YBCO single crystal using the dc flux transformer geometry in case of the applied magnetic field up to 7.5T parallel to the c axis. The results show that the V \-\{top\}= V \-\{bot\} is not observed in the range of the resolution of voltmeter for various magneti c fields, namely V \-\{top\}> V \-\{bot\}. The ratio of V \-\{top\}/ V \-\{bot\} in various magnetic fields changes with the temperature decreasing. The temperature dependence of resistivity along c axis is consistent with that in ab plane. The critical temperature T\+c\-c along the c axis is higher than that in ab plane, indicating that the coupling between the layers is stronger as the temperature decreases and 3 D character is in the lower temperature.

关 键 词：超导体 织构 耦合 磁通 超导电性 热激活 

分 类 号：O514[理学—低温物理] O511.2[理学—物理]