铝、碳共掺提高MgB_2临界电流密度  

IMPROVING CRITICAL CURRENT DENSITY OF MgB_2 BY CODOPING WITH C AND Al

作　　者：杨烨[1] 周杰俤[1] 崔雅静[1] 张勇[1] 赵勇[1] 

机构地区：[1]磁浮技术与磁浮列车教育部重点实验室西南交通大学超导研究开发中心

出　　处：《低温物理学报》2009年第1期20-24,共5页Low Temperature Physical Letters

基　　金：国家自然科学基金项目(项目编号:50372052;50588201);国家重大基础研究项目(973)(项目编号:2007CB616906);长江学者和创新团队发展计划项目(项目编号:IRT0751);西南交通大学青年教师科研起步基金(项目编号:2007Q014)资助~~

摘　　要：本文研究了在MgB2超导体中Al,C及两种元素共同掺杂时对样品的超导转变温度,不可逆场和临界电流的影响.研究发现,少量的铝掺杂可以提高MgB2超导材料在低场下的临界电流密度,但由于对Tc的抑制而降低其在高场下的载流能力,而碳掺杂则可以有效提高MgB2超导材料的上临界场和不可逆场,从而达到改善其在高场下的载流能力的目的.研究发现,在0～7T外磁场范围内,1%铝和1%碳共同掺杂的样品表现出最佳的载流性能,钉扎力曲线的分析也应证了这一结果.The influence of the Carbon and Aluminum doping on Tc, Hirr and Jc of MgB2 superconductor has been presented. The observed decrease of Tc of samples could be attributed to the band filling effect and interband scattering. It was found that Jc of samples was enhanced by low level aluminium doping in low field region, however its ability of carrying current was weakened in high field region capering with pristine one. On the other hand, carbon doping could significantly increase the Jc of doped MgB2 in high field region due to improvement of He2 and Hirr. In this paper we presented that the MgB2 codoped with 1% carbon and 1% aluminium shown the best performance in the whole range of a pplied magnetic field. This result is consistent with the analysis of flux pinning force density of all samples.

关 键 词：MGB2 二硼化镁 磁通钉扎 

分 类 号：TM26[一般工业技术—材料科学与工程] TN304.21[电气工程—电工理论与新技术]