First Investiation of magnetic ground states in the rare-earth intermetallic compounds RAl$_{0.9}$Si$_{1.1}$ (R = Ce, Pr, Gd)

TL;DR

This study investigates the magnetic ground states of newly discovered ternary rare-earth intermetallic compounds RAl$_{0.9}$Si$_{1.1}$, revealing diverse magnetic behaviors depending on the rare-earth element, including ferromagnetism and antiferromagnetism.

Contribution

First detailed investigation of magnetic properties in RAl$_{0.9}$Si$_{1.1}$ compounds, highlighting element-dependent magnetic ground states and responses to magnetic fields.

Findings

Ce compound shows weak ferromagnetism below 11 K

Pr compound orders ferromagnetically at 17 K

Gd compound is antiferromagnetic with T_N = 30.5 K

Abstract

We report the magnetic properties strongly varying with the rare-earth elements in the newly found ternary compounds $R$Al$_{0.9}$Si$_{1.1}$, which crystallize in the tetragonal $\alpha$-ThSi$_2$-type structure. For $R$ = Ce the alloy has a weak ferromagnetism below 11 K and for $R$ = Pr it orders ferromagnetically at 17 K, while for $R$ = Gd it is antiferromagnetic with $T_{\rm N}$ = 30.5 K. In addition, we find no field effect on $T_{\rm N}$ of $R$ = Gd because of the large internal mean field, but significant changes in the magnetic properties of $R$ = Ce and Pr.