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Updated: Jul 19, 2025
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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
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Vanishing RKKY interactions in Ce-based cage compounds
A M Konic1, Y Zhu2,3, A J Breindel2,3
1Department of Physics, Kent State University, Kent, OH 44242, United States of America.
Summary
Thermodynamic measurements reveal the Γ7 doublet as the ground state in cubic Ce-based compounds. This explains the absence of long-range magnetic order at low temperatures due to vanishing Ruderman-Kittel-Kasuya-Yosida interactions.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Magnetism
Background:
- Cubic Ce-based cage compounds (CeT2Cd20, T=Ni, Pd) are investigated for their magnetic properties.
- Understanding the ground state and interactions in these materials is crucial for predicting their magnetic behavior.
Purpose of the Study:
- To determine the ground state multiplet of Ce3+ ions in CeT2Cd20 compounds.
- To investigate the role of Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in the absence of long-range magnetic order.
Main Methods:
- Thermodynamic measurements, specifically heat capacity, were performed in an external magnetic field.
- Analysis of heat-capacity data to identify the ground state and excited states.
Main Results:
- The Γ7 doublet was identified as the ground state multiplet for Ce3+ ions.
- Theoretical analysis indicates that the RKKY interaction vanishes at low temperatures for the Γ7 ground state.
Conclusions:
- The vanishing RKKY interaction in CeT2Cd20 compounds explains the lack of observed long-range magnetic order down to millikelvin temperatures.
- These findings contribute to the understanding of quantum criticality and frustrated magnetism in Ce-based intermetallic compounds.
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