铁基超导薄膜研究进展  

Recent development of iron-based superconducting films

作　　者：樊帆 张现平[1,2] 徐中堂 马衍伟[1,2] Fan Fan;Xianping Zhang;Zhongtang Xu;Yanwei Ma(Key Laboratory of Applied Superconductivity,Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院电工研究所应用超导重点实验室,北京100190 [2]中国科学院大学工程科学学院,北京100049

出　　处：《科学通报》2021年第19期2416-2429,共14页Chinese Science Bulletin

基　　金：国家自然科学基金(51861135311,U1832213,51607174,51721005);中国科学院国际合作局对外合作重点项目(GJHZ1775,182111KYSB20160014);中国科学院前沿科学重点研究项目(QYZDJ-SSW-JSC026);中国科学院战略性先导科技专项(XDB25000000)资助;国家重点研发计划(2018YFA0704200)。

摘　　要：铁基超导体作为一类新的高温超导体,由于其独特的性质以及与铜氧化物和传统超导体的显著区别而备受关注.铁基超导体具有比铜氧化物超导体更小的各向异性、较高的超导临界转变温度和上临界场,因此在超导薄膜的制备及应用方面具有很多优势.除此以外,铁基超导薄膜的其他特性,如其外延薄膜具有比块体样品更高的超导临界转变温度,可以形成常规固相反应条件下无法获得的亚稳相等,也引起了研究者的兴趣.本文重点论述了LnFeAs(O,F)(Ln=镧系元素)、掺杂的AEFe_(2)As_(2)(AE=碱土金属)、FeCh(Ch=硫族元素)3个体系在薄膜方面取得的成果,总结分析了铁基超导薄膜的生长、微观结构和性能之间的潜在联系,分别从铁基超导薄膜的制备、晶格结构与超导临界转变温度的关系、薄膜缺陷生长与临界电流密度的联系,以及辐照对薄膜性能的影响等方面介绍了铁基超导薄膜的研究进展.The discovery of F-doped LaFeAsO in 2008 brought a worldwide research surge of iron-based superconductors.As a new type of high-temperature superconductors,iron-based superconductors have attracted much attention due to their unique properties and significant differences from copper oxide and traditional superconductors.Iron-based superconductors have small anisotropy,high superconducting transition temperature and upper critical field,which are preferred in film preparation and applications.At the same time,the features of iron-based superconductor films,such as higher superconducting transition temperature in epitaxial films and the ability to stabilize metastable equivalents,are interesting to the researchers.The studies on films are very useful for the basic research on superconducting physics and the search of new superconducting materials.The iron-based superconductors discovered so far can be divided into four systems:(1)1111 system:LnFeAs(O,F)(Ln=lanthanides);(2)122 system:AEFe_(2)As_(2)(AE=alkaline earth metals);(3)111 system:LiFeAs and NaFeAs;(4)11 system:FeCh(Ch=chalcogenides).1111 system is the first reported iron-based superconductor.It has a high critical transition temperature up to 58 K as well as a higher upper critical field.The disadvantage of 1111 superconductors is the lager anisotropy and the broadened superconducting transition under the magnetic field.The critical transition temperature of 122 system is lower than 1111 system,but it can still reach 38 K,and its anisotropy and elemental stability is better than 1111 system.The structure of 11 system is the simplest in iron-based superconductor family.It contains no toxic element As,but the transition temperature is low(8 K).111 system is unstable in the air,limiting its application prospects.In addition,the critical current density is very important for the application of superconductors,which has been obtained in 122-system superconducting tapes.Meanwhile,the 11-system superconducting film stands out because of its easy growth,simple struc

关 键 词：铁基超导体 晶体结构 缺陷 辐照 临界转变温度 临界电流密度 

分 类 号：O511.3[一般工业技术—材料科学与工程]