镁扩散法制备Pr_6O_(11)掺杂的MgB_2块体的临界电流密度和磁场性能（英文）

Improved Critical Current Density and Magnetic Properties of Pr_6O_(11)-doped MgB_2 Bulks Synthesized by Mg-diffusion Method

采用镁扩散法制备了Pr_6O_(11)纳米颗粒掺杂的Mg B_2超导块体,研究了Pr_6O_(11)掺杂对其临界电流密度(J_c),不可逆磁场(H_(irr))和上临界磁场(H_(c2))的影响。实验结果表明,Pr_6O_(11)纳米颗粒掺杂明显提高了块体的J_c,H_(irr)和H_(c2),但没有降低其超导转变温度T_c。在20 K自场条件下,质量分数为1%Pr_6O_(11)掺杂Mg B_2块体的J_c为未掺杂样品的近5倍,J_c=3.61×10~5A/cm^2。在10 K温度下,Mg B_2块体H_(c2)和H_(irr)较未掺杂样品分别提高了1.9和2.6 T。同时讨论了Pr_6O_(11)纳米颗粒掺杂对MgB_2块体的超导性能和磁通钉扎机制的影响。

The effects of the addition of Pr6O11 nanopowder on the critical current density（Jc）,irreversible field（Hirr）and upper critical field（Hc2）of the MgB2 bulks prepared by a Mg-diffusion method were investigated.The results show that the Pr6O11 nanopowder doping can significantly enhance the J_（c,）Hirr and Hc2 of the MgB2 bulks,but has little effect on the superconducting transition temperature（Tc）.At 20 K in a self-field,the Jc value of the 1 wt%Pr6O11-doped MgB2 sample is 3.61×10^5 A/cm^2,which is nearly 5 times larger than that of the undoped sample.In addition,at 10 K,the Hc2 and Hirr of the bulk increase by 1.9 and 2.6 T,respectively.The effect of Pr6O11-doping on superconductivity and flux pinning mechanism was also discussed.