Large magnetoresistance in the magnetically ordered state as well as in the paramagnetic state near 300 K in an intermetallic compound,Gd7Rh3

TL;DR

This study reveals large magnetoresistance in Gd7Rh3 both in its antiferromagnetic and paramagnetic states near 300 K, driven by magnetic field-induced changes in electrical resistivity.

Contribution

It demonstrates significant magnetoresistance in Gd7Rh3 at high temperatures, including in the paramagnetic state, which is uncommon for such compounds.

Findings

Large magnetoresistance near room temperature in Gd7Rh3

Magnetoresistance increases as temperature decreases

Giant magnetoresistance observed above 77 K due to metamagnetic transition

Abstract

We report the response of electrical resistivity $\rho$ to the application of magnetic fields (H) up to 140 kOe in the temperature interval 1.8-300 K for the compound, Gd7Rh3, ordering antiferromagnetically below 150 K. We find that there is an unusually large decrease of $\rho$ for moderate values of H in the close vicinity of room temperature uncharacteristic of paramagnets, with the magnitude of the magnetoresistance increasing with decreasing temperature as though the spin-order contribution to $\rho$ is temperature dependent. In addition, this compound exhibits giant magnetoresistance behaviour at rather high temperatures (above 77 K) in the magnetically ordered state due to a metamagnetic transition.