Electronic structure of NaFeAs superconductor: LDA+DMFT calculations compared with ARPES experiment

TL;DR

This study uses LDA+DMFT calculations to analyze the electronic structure of NaFeAs, showing strong correlation effects consistent with ARPES experiments and clarifying the orbital contributions and kz dependence.

Contribution

The paper demonstrates that correlation effects alone explain the ARPES data for NaFeAs without additional bosonic interactions, providing detailed orbital and kz insights.

Findings

Effective mass renormalization factor of about 3 matches ARPES data.

Correlation effects on Fe-3d orbitals are sufficient to explain experimental observations.

ARPES beam energy correlates with specific kz values in the Brillouin zone.

Abstract

We present the results of extended theoretical LDA+DMFT calculations for a new iron-pnictide high temperature superconductor NaFeAs compared with the recent high quality angle-resolved photoemission (ARPES) experiments on this system [1]. The universal manifestation of correlation effects in iron-pnictides is narrowing of conducting bands near the Fermi level. Our calculations demonstrate that for NaFeAs the effective mass is renormalized on average by a factor of the order of 3, in good agreement with ARPES data. This is essentially due to correlation effects on Fe-3d orbitals only and no additional interactions with with any kind of Boson modes, as suggested in [1], are necessary to describe the experiment. Also we show that ARPES data taken at about 160 eV beam energy most probably corresponds to $k_z=\pi$ Brillouin zone boundary, while ARPES data measured at about 80 eV beam energy rather represents $k_z=0$. Contributions of different Fe-3d orbitals into spectral function map are also discussed.