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Published on: June 7, 2018
Zero-temperature magnetic transition in an easy-axis Kondo lattice model
Jian-Xin Zhu1, Stefan Kirchner, Ralf Bulla
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Physical Review Letters
|February 1, 2008
Summary
This study investigates quantum transitions in an antiferromagnetic Kondo lattice model. Results reveal a destruction of Kondo screening and a second-order quantum phase transition at zero temperature.
Area of Science:
- Condensed Matter Physics
- Quantum Magnetism
Background:
- Kondo lattice models describe the interaction between localized magnetic moments and conduction electrons.
- Antiferromagnetic ordering and easy-axis anisotropy introduce complex magnetic behaviors.
- Understanding quantum phase transitions is crucial for developing novel electronic materials.
Purpose of the Study:
- To investigate the quantum phase transition in a spin-1/2 antiferromagnetic Kondo lattice model with easy-axis anisotropy.
- To analyze the destruction of Kondo screening and characterize the nature of the transition.
- To compare results from different theoretical methods for validation.
Main Methods:
- Extended dynamical mean-field theory (DMFT) was employed.
- Bosonic numerical renormalization group (BNRG) method was used for real-frequency calculations.
- Results were compared with quantum Monte Carlo (QMC) simulations in Matsubara frequency.
Main Results:
- BNRG calculations showed a logarithmic divergence in critical local spin susceptibility.
- This divergence indicates the destruction of Kondo screening.
- The zero-temperature transition was found to be consistent with second-order characteristics.
Conclusions:
- The study successfully characterized the quantum transition and destruction of Kondo screening.
- The findings provide insights into the complex interplay of magnetism and electronic correlations.
- Further microscopic studies are suggested to explore subtle features observed in the results.
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