Disorder correction to the N\'{e}el temperature of ruthenium-doped BaFe$_2$As$_2$: Theoretical analysis

TL;DR

This paper provides a theoretical analysis of how disorder from ruthenium doping affects the Neel temperature in BaFe2As2, showing that the temperature remains largely unaffected by doping-induced disorder.

Contribution

The study introduces a perturbation theory approach to estimate disorder effects on the Neel temperature in ruthenium-doped BaFe2As2, demonstrating its insensitivity to disorder.

Findings

Disorder-induced correction to Neel temperature is small.

Neel temperature is insensitive to Ru doping-induced disorder.

Theoretical estimates align with experimental observations.

Abstract

We analyze theoretically nuclear magnetic resonance data for the spin-density wave phase in the ruthenium-doped BaFe$_2$As$_2$. Since inhomogeneous distribution of Ru~atoms introduces disorder into the system, experimentally observable random spatial variations of the spin-density wave order parameter emerge. Using perturbation theory for the Landau functional, we estimate the disorder-induced correction to the N\'{e}el temperature for this material. Calculated correction is significantly smaller than the N\'{e}el temperature itself for all experimentally relevant doping levels. This implies that the N\'{e}el temperature is quite insensitive to the disorder created by the dopants.