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Work statistics for sudden quenches in interacting quantum many-body systems
Eric G Arrais1, Diego A Wisniacki2, Augusto J Roncaglia2
1Instituto de Física, Universidade Federal do Rio de Janeiro, 21941-972 Rio de Janeiro, Brazil.
Physical Review. E
|December 25, 2019
Summary
Researchers developed a simple method to describe work probability distributions in quantum systems undergoing sudden quenches. This approach uses initial Hamiltonian level density and a smoothed strength function for accurate predictions.
Area of Science:
- Quantum mechanics
- Statistical mechanics
- Condensed matter physics
Background:
- Work distribution in isolated quantum systems follows fluctuation theorems (Crooks, Jarzynski).
- Describing these distributions for sudden quenches in large systems is complex.
Purpose of the Study:
- To provide a simplified method for calculating work probability distribution functions in quantum systems after sudden quenches.
- To develop a model applicable to quantum many-body interacting systems.
Main Methods:
- Utilizing the level density of the initial Hamiltonian.
- Employing a smoothed strength function to capture perturbation effects on eigenvectors.
- Applying random models to determine the smoothed work probability distribution.
- Testing the approach on one-dimensional spin-1/2 chain models.
Main Results:
- The proposed method accurately describes work distributions in sudden quench processes.
- The approach is effective for systems with large Hilbert spaces.
- Valid for intermediate and high temperatures in both chaotic and integrable regimes.
Conclusions:
- A straightforward yet accurate method for work distribution analysis in quantum systems is presented.
- The combination of level density and smoothed strength function offers a powerful tool.
- Findings are relevant for understanding non-equilibrium quantum dynamics in various systems.
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