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Updated: Aug 9, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Can Competition between the crystal field and the Kondo effect cause non-Fermi-liquid-like behavior?
Frithjof B Anders1, Thomas Pruschke
1Theoretical Physics, University of the Saarland, 66041 Saarbrücken, Germany.
Physical Review Letters
|April 12, 2006
Summary
Unusual magnetic behavior in Ce(1-x)La(x)Ni9Ge4 suggests a non-Fermi-liquid state. Crystal-field splitting leads to a crossover between SU(4) and SU(2) Kondo effects, influencing magnetic susceptibility and specific heat.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Magnetism
Background:
- Unusual magnetic susceptibility and specific heat observed in Ce(1-x)La(x)Ni9Ge4.
- These properties raise questions about a potential non-Fermi-liquid ground state.
Purpose of the Study:
- To explain the observed physical phenomena in Ce(1-x)La(x)Ni9Ge4.
- To investigate the role of crystal-field splitting in the Ce 4f-shell.
Main Methods:
- Theoretical analysis incorporating crystal-field splitting of magnetic doublets.
- Modeling the crossover between SU(4) and SU(2) Kondo effects.
Main Results:
- A consistent physical picture requires considering crystal-field splitting.
- A crossover between SU(4) and SU(2) Kondo effects is observed for specific splitting magnitudes.
- Differential screening of magnetic doublets impacts low-temperature properties.
Conclusions:
- The observed behavior is explained by a crossover in Kondo effects due to crystal-field splitting.
- Low-temperature properties are strongly influenced by the temperature scales of doublet screening.
- Experiments down to 50 mK probe an extended crossover towards a strong-coupling Fermi-liquid fixed point.
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