Magnetic properties of PrPd$_{2}$Si$_{2}$ and PrPt$_{2}$Si$_{2}$

TL;DR

This study compares the magnetic properties of PrPd₂Si₂ and PrPt₂Si₂, revealing antiferromagnetic order in the former and non-magnetic behavior in the latter due to differences in crystal electric field schemes and structure.

Contribution

It provides new insights into how crystal structure influences magnetic ground states and properties in Pr-based intermetallic compounds.

Findings

PrPd₂Si₂ orders antiferromagnetically at 3 K.

PrPt₂Si₂ shows no magnetic order down to 2 K.

Large magnetoresistance observed in PrPd₂Si₂.

Abstract

We have investigated the two rare-earth intermetallic compounds PrPd$_{2}$Si$_{2}$ and PrPt$_{2}$Si$_{2}$ by means of magnetization, electrical resistivity and heat capacity measurements. While PrPd$_{2}$Si$_{2}$ exhibits an antiferromagnetic ordering at 3 K, no magnetic ordering is observed in PrPt$_{2}$Si$_{2}$ down to 2 K. The different magnetic behaviors of these two compounnds are due to different crystalline electric field (CEF) level schemes. The specific heat data suggest a quasi-quartet ground state in PrPd$_2$Si$_2$ in contrast to a nonmagnetic singlet ground state in PrPt$_2$Si$_2$. This difference is attributed to the loss of a mirror plane upon changing the crystal structure from the ThCr$_2$Si$_2$ type (PrPd$_2$Si$_2$) to the CaBe$_2$Ge$_2$ type (PrPt$_2$Si$_2$). Further on, a large magnetoresistance is also observed in the magnetically ordered state of PrPd$_2$Si$_2$.