Physical properties of Ce3-xTe4 below room temperature

TL;DR

This study investigates the magnetic, thermal, and thermoelectric properties of Ce3-xTe4 across different compositions, revealing magnetic ordering driven by RKKY interactions and phonon-electron scattering effects on thermal conductivity.

Contribution

It provides new insights into the magnetic and thermoelectric behavior of Ce3-xTe4, especially how composition influences magnetic order and thermal transport.

Findings

Ce3-xTe4 exhibits a ferromagnetic transition near 4K in the x=0 compound.

Magnetic order is suppressed with increased x, indicating RKKY interaction dependence.

Lattice thermal conductivity remains near 1.2 W/m/K at 200K across compositions.

Abstract

The physical properties of polycrystalline Ce3-xTe4 were investigated by measurements of the thermoelectric properties, Hall coefficient, heat capacity, and magnetization. The fully-filled, metallic x=0 compound displays a soft ferromagnetic transition near 4K, and analysis of the corresponding heat capacity anomaly suggests a doublet ground state for Ce^{3+}. The transition is suppressed to below 2K in the insulating x=0.33 composition, revealing that magnetic order in Ce3-xTe4 is driven by an RKKY-type interaction. The thermoelectric properties trend with composition as expected from simple electron counting, and the transport properties in Ce3Te4 are observed to be similar to those in La3Te4. Trends in the low temperature thermal conductivity data reveal that the phonons are efficiently scattered by electrons, while all compositions examined have a lattice thermal conductivity near 1.2W/m/K at 200K.