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Chaos and Thermalization in the Spin-Boson Dicke Model
David Villaseñor1,2, Saúl Pilatowsky-Cameo3, Miguel A Bastarrachea-Magnani4
1Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apdo. Postal 70-543, Mexico City 04510, Mexico.
Entropy (Basel, Switzerland)
|January 21, 2023
Summary
Chaos drives thermalization in the spin-boson Dicke model. The study validates the eigenstate thermalization hypothesis (ETH) in chaotic regions, confirming thermalization and showcasing the efficient basis for analysis.
Area of Science:
- Quantum mechanics
- Statistical physics
- Condensed matter theory
Background:
- The spin-boson Dicke model exhibits both regular and chaotic dynamics.
- Understanding thermalization in quantum systems is crucial for various physical phenomena.
Purpose of the Study:
- To analyze the link between chaos and thermalization in the Dicke model.
- To validate the eigenstate thermalization hypothesis (ETH) in chaotic regimes.
Main Methods:
- Analysis of eigenstate expectation values and distributions.
- Application of von Neumann and Shannon entropies.
- Comparison of Fock and efficient bases for spectral analysis.
Main Results:
- Diagonal and off-diagonal ETH are validated in the chaotic region, confirming thermalization.
- Chaotic eigenstates are characterized by their structure.
- The efficient basis offers advantages over the Fock basis for analyzing the Dicke model's unbounded spectrum.
Conclusions:
- Chaos is a key ingredient for thermalization in the Dicke model.
- The ETH framework successfully describes thermalization in chaotic Dicke model eigenstates.
- The efficient basis is a more suitable tool for investigating the Dicke model's spectral properties.
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