铁基高温超导体研究进展

New iron-pnictide superconductors

最近,由于在铁基Ln(O,F)FeAs化合物及其相关化合物中发现具有高于40K的超导电性,层状的铁基化合物引起了凝聚态物理学界很大的兴趣和关注.在随后的研究中发现,在该类材料中最高超导临界温度可达到55K.这些重要的发现使得人们又重新对高温超导体的探索产生了极大的兴趣,并且为研究高温超导的机理提供了新的一类材料.文章主要介绍了作者所在组在新型铁基超导体方面的最新研究进展,包括:(1)铁基超导材料探索研究;(2)铁基超导体的单晶制备及物性研究;(3)铁基超导体的电子相图及自旋密度波(SDW)和超导共存研究;(4)同位素交换对超导转变和SDW转变的效应.最后,在已完成的工作基础上提出了一些今后的研究方向和发展前景.

The discovery of superconductivity with a critical temperature （To） higher than 40 K in the iron arsenide Ln（O, F）FeAs has drawn much interest in condensed matter physics. Later discoveries, including the enhancement of Tc up to 55 K, has evoked intense excitement in the pilgrimage towards the understanding of the mechanism of high Tc superconductivity, while providing a brand new family of materials to address this issue. In this review we present our group＇s major research on new iron based superconductors, including： （1） our initial investigations; （2） the synthesis of iron arsenide single crystals and the characterization of its physical properties; （3） the electronic phase diagram of iron based superconductors and the coexistence between spin density waves and superconductivity; （4） the effect of isotope exchange on spin density waves and superconducting transitions. To finish, we propose possible future directions in this field.