MgB_2超导体掺杂的理论研究  

THEORETICAL STUDY ON THE SUPERCONDUCTOR OF R-DOPING IN BULK MgB_2 SAMPLES

作　　者：陈团结[1] 孙爱民[1] 张汉谋[1] 沈东星[1] 朱海滨[1] 李彦炜[1] 

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070

出　　处：《低温物理学报》2006年第3期232-235,共4页Low Temperature Physical Letters

基　　金：国家自然科学基金(批准号:60276015)资助的课题~~

摘　　要：由双带模型,在BCS理论的框架内,唯象地引进调制势函数Ф,研究了固溶体Mg1-xRxB2和MgRxB2-x(R为某掺杂元素)的超导临界温度,我们看到在Ф=0.2处出现了一个超导临界温度Tc峰,这显然与掺杂的物质种类、比率及均匀程度有关,我们的研究结果与M.J.Mehl等人1根据BCS理论密度方程计算基本一致,也与杨帆等人2通过ab initio计算相吻合.对已有实验结果的拟合发现,目前实验制备出的MgB2型超导体的Ф值均已大于0.4.这些结果为我们今后的实验研究工作提供了一个可供参考的研究方向.Based on two-band model, the modulated potential function Ф is introduced according to BCS theory phenomenologically. The superconductivity transition temperature of superconductor Mg1-x RxB2 and MgRx B2-x have been studied by using the consistent method. The results of the calculations are in agreement with Refe. A maximum of the superconductivity critical temperature Tc is found at Ф= 0. 2 , which is related to the doping elements , ratio of doping mass and the doping uniformity. These results provide a referable researching direction for us.

关 键 词：超导固溶体 双带模型 BCS理论 临界温度 

分 类 号：O511.2[理学—低温物理]