C、Cu掺杂对MgB_2超导电性的影响  

C,Cu-DOPING EFFECTS ON THE STRUCTURAL CHANG MgB_2

作　　者：魏桂丹[1] 孙爱民[1] 平学琦 马金元[1] 郑龙[1] 

机构地区：[1]西北师范大学物理与电子工程学院,兰州730070 [2]黑龙江省佳木斯市第十一中学,黑龙江佳木斯154004

出　　处：《低温物理学报》2010年第4期317-320,共4页Low Temperature Physical Letters

摘　　要：本文利用固相烧结法制备了一系列碳(C)、铜(Cu)掺杂的二硼化镁(MgB2)样品,并对样品进行细致的分析.X射线衍射图表明随着C掺杂量的增加c轴方向晶格常数几乎不变,a轴方向晶格常数略有减小,c/a随C掺杂量的增加逐渐增大,由此估算出了C的实际替代量,推测出此条件下C在MgB2中溶解度在12.5%和15%之间.电阻随温度变化关系(R～T)表明在Cu的掺杂量确定时,转变温度(Tc)随C的掺杂量的增大而降低。A series of samples of [Mg（B1-xCx）2]0.97Cu0.03（x=0.00,0.05,0.10,0.15,0.20,0.25）and MgB2 were synthesized by a solid state reaction method and analyzed carefully these samples.The XRD result indicates that thec-axis of the lattice remains unchanged with increasing C doping,while the a-axis shows a small decrease.The real carbon content x is estimated from the lattice parameter,and the solubility limit for C in MgB2 presumed lies between 12.5% and 15%.The R～Tresult indicates when the C content remains unchanged,the superconducting transition temperature（Tc）of samples steadily decreases with increasing C doping.

关 键 词：MGB2 掺杂 晶格常数 转变温度 

分 类 号：O511[理学—低温物理]