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Quantum limit to nonequilibrium heat-engine performance imposed by strong system-reservoir coupling
David Newman1,2, Florian Mintert2, Ahsan Nazir1
1Department of Physics and Astronomy, The University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom.
Physical Review. E
|June 25, 2020
Summary
Finite system-reservoir coupling limits quantum heat engine performance by generating coherence. This quantum effect hinders power output and efficiency, going beyond standard Born-Markov analysis.
Area of Science:
- Quantum thermodynamics
- Nonequilibrium quantum systems
- Quantum heat engines
Background:
- Quantum heat engines offer a theoretical framework for energy conversion at the quantum level.
- Understanding performance limits is crucial for developing practical quantum technologies.
- Standard models often assume weak system-reservoir coupling (Born-Markov approximation).
Purpose of the Study:
- To investigate the impact of finite system-reservoir coupling on quantum heat engine performance.
- To identify quantum limits imposed by system-reservoir interactions.
- To explore phenomena beyond the Born-Markov approximation.
Main Methods:
- Theoretical analysis of a quantum heat engine model.
- Inclusion of finite system-reservoir coupling effects.
- Investigation of coherence generation in the working system's energy eigenstates.
Main Results:
- Finite system-reservoir coupling introduces a distinct quantum performance limit.
- Correlations induced by coupling generate coherence between energy eigenstates.
- This coherence significantly hampers engine power output and efficiency.
Conclusions:
- Finite system-reservoir coupling is a critical factor limiting quantum heat engine performance.
- Coherence generation due to coupling is a key mechanism, not captured by Born-Markov theory.
- This finding necessitates advanced theoretical approaches for accurate quantum engine modeling.
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