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Updated: Jul 24, 2025
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
8.6K
Metamagnetic transition in the twoforbitals Kondo lattice model
Christopher Thomas1, Sébastien Burdin2, Claudine Lacroix3
1Instituto de Física, UFRGS, 91501-970 Porto Alegre, Brazil.
Summary
This study explores a two-orbital Kondo lattice model under a transverse magnetic field. Ferromagnetism and the Kondo effect coexist at low fields, with metamagnetic transitions observed as the field increases.
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Systems
- Materials Science
Background:
- Kondo lattice models describe interactions between localized f-electrons and conduction electrons.
- Uranium systems often exhibit mixed localization and delocalization of f-electrons.
- Magnetic fields significantly influence electronic properties in magnetic materials.
Purpose of the Study:
- Investigate the interplay of ferromagnetism and Kondo effect in a two-orbital f-electron system.
- Analyze the impact of a transverse magnetic field on this model.
- Characterize magnetic transitions in the presence of Kondo coupling.
Main Methods:
- Theoretical study of a Kondo lattice model with two f-orbitals.
- Inclusion of Hund's coupling and intersite exchange interactions.
- Analysis of localized (orbital 1) and delocalized (orbital 2) f-electron behaviors.
- Examination of the system's response to a transverse magnetic field at low temperatures (T→0).
Main Results:
- Coexistence of ferromagnetism and the Kondo effect is found for small transverse magnetic fields.
- As the transverse field increases and Kondo coupling vanishes, two distinct metamagnetic transition scenarios emerge.
- These transitions occur either before or concurrently with the fully polarized state, or after spins align with the field.
Conclusions:
- The model provides a framework for understanding complex magnetic behaviors in f-electron systems.
- Transverse magnetic fields can induce rich phase transitions, including metamagnetism.
- The coexistence of ferromagnetism and Kondo effect is a key feature at low fields.
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