Satellites and large doping- and temperature-dependence of electronic properties in hole-doped BaFe2As2

TL;DR

This paper investigates the impact of dynamical Coulomb screening on the electronic properties of hole-doped BaFe2As2, revealing strong doping- and temperature-dependent behaviors and unconventional self-energy effects.

Contribution

It introduces the consideration of dynamical Coulomb screening effects in iron-based superconductors, highlighting their influence on electronic structure and correlation phenomena.

Findings

Dynamical screening affects low-energy electronic structure and correlation satellites.

Hole overdoped BaFe2As2 exhibits incoherent metallic behavior.

Optimal doping shows unconventional square-root energy dependence in self-energy.

Abstract

Over the last years, superconductivity has been discovered in several families of iron-based compounds. Despite intense research, even basic electronic properties of these materials, such as Fermi surfaces, effective electron masses, or orbital characters are still subject to debate. Here, we address an issue that has not been considered before, namely the consequences of dynamical screening of the Coulomb interactions among Fe-d electrons. We demonstrate its importance not only for correlation satellites seen in photoemission spectroscopy, but also for the low-energy electronic structure. From our analysis of the normal phase of BaFe2As2 emerges the picture of a strongly correlated compound with strongly doping- and temperature-dependent properties. In the hole overdoped regime, an incoherent metal is found, while Fermi-liquid behavior is recovered in the undoped compound. At optimal doping, the self-energy exhibits an unusual square-root energy dependence which leads to strong band renormalizations near the Fermi level.