铁基超导体的角分辨光电子能谱研究进展

Angle resolved photoemission spectroscopy of iron pnictides

最近发现的超导转变温度高达55K铁基高温超导体结束了铜氧化物在超导转变温度高于40K的领域一统天下的局面.与铜氧化物高温超导体一样,超导配对对称性对于理解这一新的体系有着重要的作用.文章利用角分辨光电子能谱实验手段,全面地研究了铁基材料的能带结构和费米面以及它们随载流子掺杂浓度变化的演化过程,发现了铁基超导体中依赖费米面的无节点的超导能隙,指出了费米面间的相互作用对超导配对起着关键作用.

The recently discovered iron pnictide compounds （critical temperature Tc = 55 K） ended the monopoly of cuprates in the family of high-Tc superconductors. As with cuprates, the pairing mechanism is important for understanding the new system. In this article, we employ high-resolution angle-resolved photoelectron spectroscopy to characterize the band structure and Fermi surface topology of iron pnictides, as well as their evolution with dopant concentration. We observe isotropie but Fermi-surface-dependent superconducting gaps in this system, and propose that inter-Fermi-surface interactions play an important role in the pairing mechanism.