About the strength of correlation effects in the electronic structure of iron

TL;DR

This paper investigates the strength of electronic correlation effects in ferromagnetic iron's electronic structure using experimental photoemission data and compares it with advanced many-body theoretical calculations, highlighting current limitations.

Contribution

It provides a detailed comparison between experimental results and state-of-the-art many-body theories, revealing the need for more refined models including non-local fluctuations.

Findings

Current theories underestimate mass renormalizations.

Theoretical scattering rates are lower than experimental observations.

Refined many-body theories are needed for accurate descriptions.

Abstract

The strength of electronic correlation effects in the spin-dependent electronic structure of ferromagnetic bcc Fe(110) has been investigated by means of spin and angle-resolved photoemission spectroscopy. The experimental results are compared to theoretical calculations within the three-body scattering approximation and within the dynamical mean-field theory, together with one-step model calculations of the photoemission process. This comparison indicates that the present state of the art many-body calculations, although improving the description of correlation effects in Fe, give too small mass renormalizations and scattering rates thus demanding more refined many-body theories including non-local fluctuations.