铁基超导体中的化学掺杂研究

SUPERCONDUCTIVITY INDUCED BY CHEMICAL DOPING IN IRON-BASED COMPOUNDS

目前已经发现的绝大部分铁基超导体都是通过化学掺杂而得到的。铁基超导体的母体一般在200 K以下经历自旋密度波(SDW)转变:即其基态是一类巡游电子反铁磁不良导体。通过适当的元素替代可以在FeAs层产生额外的电子、空穴、巡游性或化学压力,从而有效地抑制SDW序,实现超导电性。本文侧重作者所在小组的相关研究结果,将铁基超导体中的元素替代研究分为FeAs层外和FeAs层内掺杂两大类,依次介绍和评述两年来国际上对4种主要铁基化合物中的化学掺杂研究进展。

Most iron-based superconductors discovered parent compounds of the iron-based superconductors undergo were obtained by chemical doping. The spin-density-wave transition below 200 K, having the ground state of itinerant antiferromagnetic bad metals. Suitable partial element substitutions introduce excess electrons, holes, itinerancy and/or chemical pressure, which suppresses the SDW ordering and realizes superconductivity. In this review, we summarize the chemical doping according to the category of out-of-FeAs-layer and in-FeAs-layer element substitutions. The related progresses on the four types of iron-based superconductors have been presented and discussed briefly.