中国物理B ›› 2004, Vol. 13 ›› Issue (8): 1353-1357.doi: 10.1088/1009-1963/13/8/031
杨万民1, R. Nicolsky2, 周廉3, 冯勇3, 张平祥3
Yang Wan-Min (杨万民)abc, Zhou Lian (周廉)b, Feng Yong (冯勇)b, Zhang Ping-Xiang (张平祥)b, R. Nicolskyc
摘要: The levitation forces under different field cooling states were measured at 77K by changing the field cooling distance Z_{fc} between a YBCO bulk and a permanent magnet. It is found that the relationship between the absolute maximum attractive force (Z_{maf}) and the corresponding gap distance (Z_{maf}) to F_{maf} can be well described by exponential laws as a function of Z_{fc}, which allow us to predict these values according to Z_{fc}. It is also found that the distance between the Z_{0fa} (gap distance corresponding to the zero force) and Z_{maf} in the ascending process is a constant value, which is closely related to the constant reduction factor of the axial component of flux density along the axial line of the magnet if Z_{maf}-Z_{0fa} is a constant value. These results are very interesting for fundamental research and helpful in practical designing and applications.
中图分类号: