熔融织构YBCO块材磁通动力学参量的磁光图像研究(II)  

STUDY ON PARAMETERS OF VORTEX DYNAMICS IN MTG YBCO BULK OBSERVED BY MAGNETO-OPTIC IMAGING(Ⅱ)

作　　者：罗康[1] 刘蕴宏[1] 谢旭[1] 罗志全[1] 高政祥[1] 肖玲[2] 任洪涛[2] 焦玉磊[2] 郑明辉[2] 

机构地区：[1]北京大学物理系,人工微结构和介观物理国家重点实验室,北京100871 [2]北京有色金属研究总院,北京100088

出　　处：《低温物理学报》2000年第5期353-357,共5页Low Temperature Physical Letters

基　　金：国家重点基础研究专项经费资助项目

摘　　要：由熔融织构YBCO块材表面剩余磁感应强度的磁光图像 ,推算出局域有效激活能U和电流密度j,进而研究磁通运动的局域效应 .在样品的边缘区域 ,U(j)符合Zeldov对数模型 ,在样品中心区域 ,U(j)应该符合Anderson Kim线性模型 .在涡旋线向样品中心运动的前沿区域 ,可以观察到电流密度随时间先升后降 .The model independent activation energy U and the current density j were determined from the magneto optic images of the remnant field on the surface of a MTG YBCO bulk. The local effect of the vortex motion in MTG YBCO bulk was analyzed. A nice fitting of Zeldov logarithmic model was obtained at the area near the sample edges. In the sample center Anderson Kim linear model should be valid. Around the front of the vortex motion towards to the sample center the supercurrent was found not decrease monotonously, but increase first, then decrease with time.

关 键 词：超导体 熔融织构 YBCO 磁通动力学参量 磁光图像 

分 类 号：TM26[一般工业技术—材料科学与工程]