Effects of Ru Substitution on Dimensionality and Electron Correlations in Ba(Fe_{1-x}Ru_x)_2As_2

TL;DR

This study uses angle-resolved photoemission spectroscopy to investigate how Ru substitution affects the electronic structure and correlations in Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$, revealing dimensional crossover and reduced electron mass renormalization.

Contribution

It provides the first systematic analysis of Ru substitution effects on Fermi surface dimensionality and electron correlations in Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$.

Findings

Crossover from 2D to 3D Fermi surfaces with Ru doping

Significant reduction in electron mass renormalization near optimal doping

Ru substitution impacts low-energy electron excitations

Abstract

We report a systematic angle-resolved photoemission spectroscopy study on Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$ for a wide range of Ru concentrations (0.15 $\leq$ \emph{x} $\leq$ 0.74). We observed a crossover from two-dimension to three-dimension for some of the hole-like Fermi surfaces with Ru substitution and a large reduction in the mass renormalization close to optimal doping. These results suggest that isovalent Ru substitution has remarkable effects on the low-energy electron excitations, which are important for the evolution of superconductivity and antiferromagnetism in this system.