铁基超导体材料和物理研究-中国材料进展

文章信息/Info

摘要:: 自从2008年初在铁砷/铁卤（FeAs/FeSe）基的材料中发现高温超导电性以来，已经有至少7种结构类型的材料被合成出来了。其中在1111体系中，电阻和磁化测量得到的超导转变温度可达56K，而且有迹象表明超导温度有可能会继续升高。在铁基超导体的正常态，很多非常规电子特性，如反铁磁和四方-正交结构相变等也被观察到。铁基超导体是典型的多带超导体，具有较长的相干长度，近三维电子特性，很高的上临界磁场和不可逆磁场和很强的磁通钉扎能力，因此它们在强磁场方面有很好的应用前景。本文简单综述了铁基超导材料的结构类型，分别对几种主要的结构类型的性质进行了描述，然后对电子配对的机理问题作了比较详尽的描述。最后结合临界电流和临界磁场行为，对铁基超导体的应用前景提出展望。

Abstract:: Since the discovery of high temperature superconductivity in the iron pnictide/ chalcogenide materials, at least there are seven related structural types have been fabricated. In the 1111 system, the highest superconducting transition temperature (Tc) measured by resistivity and magnetization can reach 56 K. There are some hints that the Tc can be increased to higher values. The iron based superconductors have multiband feature. Many unconventional electronic properties in the normal state of iron based superconductors have been discovered. The iron based superconductors have relatively longer coherence length, more three dimensional electronic property, higher upper critical field and irreversibility field, very strong flux pinning, therefore they have the great potential for applications for producing high magnetic field. In this short overview, we will give a brief survey about the development of materials and physics of iron based superconductors. We give detailed descriptions on the properties for several kinds of materials with the major structures. In addition, we will give a introduction about the present understanding of the pairing mechanism. Finally we will try to give a perspective on the potential applications of the iron based superconductors.