Role of Fe substitution on the anomalous magnetocaloric and magnetoresistance behavior in Tb(Ni1-xFex)2 compounds

TL;DR

This study investigates how Fe substitution in Tb(Ni1-xFex)2 compounds affects their magnetic, magnetocaloric, and magnetoresistance properties, revealing increased transition temperatures and broadening of MCE peaks due to Tb moment randomization.

Contribution

It demonstrates the impact of Fe substitution on magnetic behavior and MCE broadening in Tb-based intermetallics, highlighting the role of Tb moment randomization.

Findings

Fe substitution increases the ordering temperature from 36 K to 124 K.

Magnetocaloric effect peaks become broader with Fe substitution.

Magnetoresistance results support the Tb moment randomization hypothesis.

Abstract

We report the magnetic, magnetocaloric and magnetoresistance results obtained in Tb(Ni1-xFex)2 compounds with x=0, 0.025 and 0.05. Fe substitution leads to an increase in the ordering temperature from 36 K for x=0 to 124 K for x=0.05. Contrary to a single sharp MCE peak seen in TbNi2, the MCE peaks of the Fe substituted compounds are quite broad. We attribute the anomalous MCE behavior to the randomization of the Tb moments brought about by the Fe substitution. Magnetic and magnetoresistance results seem to corroborate this proposition. The present study also shows that the anomalous magnetocaloric and magnetoresistance behavior seen in the present compounds is similar to that of Ho(Ni,Fe)2 compounds.