Search and identification of repeated magnetic compensation in Nd(1-x)R(x)Al(2) (R = Gd, Tb) series

TL;DR

This study investigates magnetic compensation phenomena in Nd(1-x)R(x)Al(2) alloys, revealing a unique repeated compensation behavior in Nd(0.8)Tb(0.2)Al(2) linked to multiple magnetic transitions and moment competition.

Contribution

It reports the first observation of repeated magnetic compensation behavior in Nd(0.8)Tb(0.2)Al(2), highlighting complex magnetic transitions and moment interactions in admixed rare-earth intermetallics.

Findings

Repeated compensation behavior observed in Nd(0.8)Tb(0.2)Al(2)

Two quasi-antiferromagnetic transitions identified upon cooling

Comparison with Nd(0.8)Gd(0.2)Rh(3)B(2) alloy

Abstract

We undertook investigations in polycrystalline R(x)R'(1-x)Al(2) alloys, in particular, explored the stoichiometries, Nd(0.8)Gd(0.2)Al(2) and Nd(0.8)Tb(0.2)Al(2), to study the magnetic compensation behavior in them in the context of contemporary interest. In these admixed rare-earth (RE) intermetallics, the compensation phenomenon is characterized by a crossover of the M = 0 axis in the low field thermomagnetic response, and a turnaround behavior due to the field-induced reversal in the orientations of the RE moments at high fields. While the characteristic attributes are present in Nd(0.8)Gd(0.2)Al(2), a repeated/multiple magnetic compensation behavior stands observed in Nd(0.8)Tb(0.2)Al(2). The ac susceptibility, the heat capacity and the transport measurements in the latter compound reveal the onset of two quasi-antiferromagnetic transitions one after the other on cooling down from the high temperature end. The two magnetic transitions involving competition between the contributions from nearly balanced weighted averages of moments of Nd{3+} and Tb{3+} ions generate the curious multiple crossings of the M = 0 axis. The results are compared and contrasted with repeated compensation behavior reported earlier in admixed Nd(0.8)Gd(0.2)Rh(3)B(2) alloy.