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Upper bound for quantum entropy production from entropy flux
1Unidade de Educação a Distância e Tecnologia, Universidade Federal Rural de Pernambuco, 52171-900 Recife, Pernambuco, Brazil.
Physical Review. E
|May 20, 2022
Summary
This study introduces a new method to estimate entropy production in complex quantum systems. The derived upper bound, based on entropy flux, simplifies calculations for nonequilibrium processes.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Non-equilibrium systems
Background:
- Entropy production quantifies irreversibility in systems not at equilibrium.
- Calculating entropy production is challenging, especially in quantum systems with complex reservoirs.
- Standard methods fail for generic non-equilibrium reservoirs.
Purpose of the Study:
- To derive a practical upper bound for entropy production.
- To relate entropy production to entropy flux for specific systems.
- To provide a tool for estimating entropy production in quantum systems.
Main Methods:
- Derivation of an upper bound for entropy production.
- Utilizing entropy flux as a computable quantity.
- Analysis of systems where flux is an observable.
Main Results:
- An upper bound for entropy production is established in terms of entropy flux.
- The bound is applicable to systems with observable fluxes.
- Demonstrated utility in a three-level maser engine and a system with a squeezed bath.
Conclusions:
- The derived bound offers a practical approach to estimate entropy production.
- This method is valuable for systems where currents (fluxes) are accessible.
- Applicable to diverse quantum non-equilibrium phenomena.
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