Electronic structure of Ba(Fe,Ru)2As2 and Sr(Fe,Ir)2As2 alloys

TL;DR

This study uses density functional calculations to analyze the electronic structures of Ba(Fe,Ru)2As2 and Sr(Fe,Ir)2As2 alloys, revealing how substitution affects their electronic properties and magnetic behavior.

Contribution

It provides a detailed computational analysis showing that Ru substitution suppresses magnetic order without doping, while Ir introduces electron doping, offering insights into alloy electronic structures.

Findings

Ru suppresses spin density wave via band width increase

Ir introduces electron doping

Alloys behave as coherent electronic systems

Abstract

The electronic structures of Ba(Fe,Ru)$_2$As$_2$ and Sr(Fe,Ir)$_2$As$_2$ are investigated using density functional calculations. We find that these systems behave as coherent alloys from the electronic structure point of view. In particular, the isoelectronic substitution of Fe by Ru does not provide doping, but rather suppresses the spin density wave characteristic of the pure Fe compound by a reduction in the Stoner enhancement and an increase in the band width due hybridization involving Ru. The electronic structure near the Fermi level otherwise remains quite similar to that of BaFe$_{2}$As$_{2}$. The behavior of the Ir alloy is similar, except that in this case there is additional electron doping.