Accurate modeling of FeSe with screened Fock exchange and Hund metal correlations

We reproduce the electronic properties of FeSe in the high-temperature phase within an ab initio framework that includes screened Fock exchange and local dynamical correlations. We robustly capture the experimental band structure, as long as the system is in the Hund metal phase. In particular, we account for the shrinking of the Fermi pockets and the sinking below the Fermi level of the hole pocket with xy orbital character. This entails the elusive correct estimate of the Sommerfeld coefficient, and supports the interpretation of noncompensated Fermi pockets seen in ARPES in terms of surface electron doping. More stringently, our modeling matches well the experimental interband optical spectrum, and captures qualitatively the temperature dependence of the thermoelectric power, extremely sensitive to the details of the bands around the Fermi level.

Automated summary

The study successfully reproduced the electronic properties of FeSe in the high-temperature phase, capturing experimental band structures and supporting interpretations of surface electron doping in ARPES studies. Additionally, the modeling matched well with interband optical spectra and qualitatively captured the temperature dependence of thermoelectric power sensitive to bands around the Fermi level.