A Reduced Moment Magnetic Ordering in a Kondo Lattice Compound: Ce8pd24ga

TL;DR

This study investigates the magnetic properties of Ce8Pd24Ga, revealing a reduced magnetic moment due to Kondo screening, with neutron and muon measurements confirming antiferromagnetic order influenced by Kondo and crystal field effects.

Contribution

First detailed neutron and muon study of Ce8Pd24Ga showing reduced magnetic moment caused by Kondo screening and elucidating its magnetic structure and underlying interactions.

Findings

Neutron diffraction shows commensurate antiferromagnetic order below 3.6K.

Magnetic moment is significantly reduced due to Kondo screening.

Magnetic properties are governed by Kondo effect, RKKY interaction, and crystal field effects.

Abstract

The magnetic ground state of the antiferromagnet Kondo lattice compound Ce8Pd24Ga has been investigated using neutron powder diffraction, inelastic neutron scattering and zero-field muon spin relaxation measurements. The neutron diffraction analysis, below TN (3.6(0.2)K), reveals a commensurate type-C antiferromagnetic structure with the ordered state magnetic moment of \~0.36 mB/Ce-atom along the cubic <111> direction. The analysis of the inelastic neutron scattering (INS) data based on the crystal field (CF) model reveals a doublet ground state with a ground state moment of 1.29 mB/Ce-atom. The observed magnetic moment from neutron diffraction, which is small compared to the expected value from CF-analysis, is attributed to screening of the local Ce moment by the Kondo effect. This is supported by the observed Kondo-type resistivity and a small change in the entropy of Ce8Pd24Ga at TN. The zero-field muon spin relaxation rate exhibits a sharp increase below TN indicating ordering of Ce moments, in agreement with the neutron diffraction data. The present studies reveal that the physical properties of Ce8Pd24Ga are governed by the onsite Kondo compensation, the moment stabilizing intersite RKKY interaction and the crystal field effect.