Magnetotransport properties in the magnetic phase of BaFe$_{2-x}$T$_x$As$_2$ (T = Co,Ni): A magnetic excitations approach

TL;DR

This study investigates the magnetotransport properties of BaFe$_{2-x}$T$_x$As$_2$ (T = Co, Ni) crystals, revealing that magnetic excitations significantly influence electronic scattering in these iron-based superconductors.

Contribution

It introduces a magnetic excitations approach to interpret magnetotransport phenomena, emphasizing magnetic scattering over multi-band conduction effects.

Findings

Magnetotransport properties are dominated by a single magnetic state.

Magnetic excitations significantly contribute to charge carrier scattering.

Samples exhibit intermediate magnetic and superconducting phases.

Abstract

Because of their complex Fermi surfaces, the identification of the physical phenomena contributing to electronic scattering in the Fe-based superconductors is a difficult task. Here, we report on the electrical resistivity, magnetoresistance, and Hall effect in two series of BaFe$_{2-x}$T$_x$As$_2$ (T = Co, Ni) crystals with different values of $x$. The T contents were chosen so that the majority of the investigated samples present an intermediate magnetically ordered state and a superconducting ground state. We interpret the obtained results in terms of scattering of charge carriers by magnetic excitations instead of describing them as resulting uniquely from effects related to multiple-band conduction. Our samples are single crystals from the structural point of view and their overall magnetotransport properties are dominated by a single magnetic state.