Crystal field influence on the thermal conductivity of the rare-earth metallic paramagnets

TL;DR

This paper investigates how crystal field effects influence the thermal conductivity in rare-earth inter-metallic paramagnets, emphasizing the role of magnetic excitations and their interplay with phonons and impurities.

Contribution

It provides a theoretical calculation of thermal conductivity considering crystal field magnetic excitations and compares results with experimental data for specific compounds.

Findings

Thermal conductivity depends on the ground state and excitation energy of magnetic ions.

Combined scattering effects from crystal-field excitations, phonons, and impurities are analyzed.

Calculated total thermal conductivity aligns with experimental measurements for REIn3 compounds.

Abstract

Contribution to thermal conductivity from conduction electron scattering on crystal field magnetic excitations is calculated and analyzed for normal rare-earth inter-metallic paramagnets. It is shown that in temperatures much lower than Debye temperature $\TD$ its behavior essentially depends on the ground state of magnetic ion in crystal field and on the excitation energy in relation to $\TD$\,. Combined effect from the electron scattering on the crystal-field excitations, on acoustic phonons, and on nonmagnetic impurities is discussed in reference to CF splitting character and to the relative intensities of magnetic and non-magnetic scattering. Total thermal conductivity resulting from these three sources of scattering is calculated for $RE$In$_3$ ($RE=\,$Nd,\,Pr,\,Tm) and compared with experimental data.