摘要
M&gnetic relaxation and magnetization of the powder melting Y_(1-x)Ho_(x)Ba_(2)Cu_(3)O_(7)(x=0.2,0.4 and 0.6)samples have been measured at the temperature of 70K.The pinning potential U and magnetization critical current density J_(c) have been obtained according to the Anderson-Kim model and Bean model.It is found that both U and J_(c) were in^uenced by doping Bb.In the sample with x=0.4 the pinning potential U has a value of 3.2 eV when the Held is equal to 1 kG and parallel to c-axis,which is the highest one we have known in the high Tc superconductors.
基金
Supported by the National Center for Research and Development on Superconductivity of China.