Orbital selective pairing and gap structures of iron-based superconductors
Orbital selective pairing and gap structures of iron-based superconductors
复制标题
DOI：
10.1103/physrevb.95.174504
复制
发表时间：
2017-05-08
影响因子：
3.7
通讯作者：
Hirschfeld, P. J.
中科院分区：
文献类型：
--
作者：
Kreisel, Andreas;Andersen, Brian M.;Hirschfeld, P. J.
讨论了铁基超导体，特别是硫系铁体系中轨道选择性强相关效应对自旋涨落配对理论的影响。我们提出改进的巡回配对理论的一个关键因素是轨道选择性，即结合占据特定轨道态的准粒子的降低相干性。这修正了通常的自旋涨落理论，通过抑制涉及较少相干态的对散射过程，并导致剩余态中电子的轨道选择性库珀对。我们表明，这种模式与实验观察到的大块和单层FeSe以及LiFeAs的各向异性间隙结构非常吻合，表明轨道选择性库珀配对在相关性更强的铁基超导体中起着关键作用。
We discuss the influence on spin-fluctuation pairing theory of orbital selective strong correlation effects in Fe-based superconductors, particularly Fe chalcogenide systems. We propose that a key ingredient for an improved itinerant pairing theory is orbital selectivity, i.e., incorporating the reduced coherence of quasiparticles occupying specific orbital states. This modifies the usual spin-fluctuation theory via suppression of pair scattering processes involving those less coherent states and results in orbital selective Cooper pairing of electrons in the remaining states. We show that this paradigm yields remarkably good agreement with the experimentally observed anisotropic gap structures in both bulk and monolayer FeSe, as well as LiFeAs, indicating that orbital selective Cooper pairing plays a key role in the more strongly correlated iron-based superconductors.