Evolution of transport properties of BaFe2-xRuxAs2 in a wide range of isovalent Ru substitution

TL;DR

This study explores how Ru substitution affects the transport properties of BaFe2-xRuxAs2, revealing a transition from non-Fermi-liquid to Fermi-liquid behavior and highlighting the role of AFM fluctuations in anomalous transport phenomena.

Contribution

It provides detailed experimental insights into the evolution of transport properties across a wide doping range, emphasizing the impact of AFM fluctuations on charge carrier scattering.

Findings

Ru substitution suppresses AFM order and induces superconductivity.

Transport properties show non-Fermi-liquid behavior near the AFM boundary.

At higher doping, transport reverts to Fermi-liquid behavior.

Abstract

The effects of isovalent Ru substitution at the Fe sites of BaFe2-xRuxAs2 are investigated by measuring resistivity and Hall coefficient on high-quality single crystals in a wide range of doping (0 < x < 1.4). Ru substitution weakens the antiferromagnetic (AFM) order, inducing superconductivity for relatively high doping level of 0.4 < x < 0.9. Near the AFM phase boundary, the transport properties show non-Fermi-liquid-like behaviors with a linear-temperature dependence of resistivity and a strong temperature dependence of Hall coefficient with a sign change. Upon higher doping, however, both of them recover conventional Fermi-liquid behaviors. Strong doping dependence of Hall coefficient together with a small magnetoresistance suggest that the anomalous transport properties can be explained in terms of anisotropic charge carrier scattering due to interband AFM fluctuations rather than a conventional multi-band scenario.