作　　者： ; ; ; ; ; ; ;

机构地区： 中国科学技术大学物理学院物理系

出　　处： 《低温物理学报》 1989年第5期353-357,共5页

摘　　要： 本文系统地研究了 Y Ba_2Pb_xCu_(3-x)O_y(0≤x≤0.4)高温超导体的正常态电阻率,交流磁化率,临界温度和临界电流密度等参量之间的关系.结果表明,在0≤x≤0.4范围内,样品的 T_c只有很小的变化,而电阻率和临界电流密度则随 x 发生显著的变化.特别是当 x=0.1时,样品的电阻率最小而相应的临界电流密度最大,在液氮温度下 J_c 为单相 Y Ba_2Cu_3O_(7-δ)样品的三倍多.作者还发现样品内界面层对临界电流的影响比超导相所占比例更大.作者应用McMillan 理论和 Ambegaokar-Baratoff 理论结果分析了实验数据. The normal resistivity,the A.C.magnetic susceptibility,the critical temperature,the critical current density and the relations of these parameters of the high-Tc superconductor YBa2 Cu3-xPbxOy have been investigated.The experimental results show that the critical transition temperatures of the sample changes slightly,but the normal resistivities and critical current densities chance remarkably as the value of x varies from 0 to 0.4.Especially at x=0.1,the sample has the lowest resistivity and hgihest critical current density.Its Jc (at 77K) is three times more than that of the single phase YBa2Cu3O7-δ sample.The authors also findthat the intergranular regions of the samples play more important roles than the voluminal fractions of the super-conductive phase in determining the critical current density.The authors have discussed the experimental data according to McMillan and Ambegaokar-Barataff theories.

关 键 词： 氧化物 钇 超导体 钡 铅 电流特性

领　　域： [电气工程] [一般工业技术]