Formation of Hubbard-like bands as a fingerprint of strong electron-electron interactions in FeSe

Article

关键词: MEAN-FIELD THEORY;    IRON CHALCOGENIDES;    SUPERCONDUCTIVITY;    FRUSTRATION;    SPECTRA;   

DOI  :  10.1103/PhysRevB.95.081106

来源: SCIE

【 摘 要 】

We use angle-resolved photoemission spectroscopy (ARPES) to explore the electronic structure of single crystals of FeSe over a wide range of binding energies and study the effects of strong electron-electron correlations. We provide evidence for the existence of Hubbard-like bands at high binding energies consisting of incoherent many-body excitations originating from Fe 3d states in addition to the renormalized quasiparticle bands near the Fermi level. Many high-energy features of the observed ARPES data can be accounted for when incorporating the effects of strong local Coulomb interactions in calculations of the spectral function via dynamical mean-field theory, including the formation of a Hubbard-like band. This shows that over the energy scale of several eV, local correlations arising from the on-site Coulomb repulsion and Hund's coupling are essential for a proper understanding of the electronic structure of FeSe and other related iron-based superconductors.

【 授权许可】

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