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Periodic thermodynamics of open quantum systems
1Department of Applied Physics, Aalto University, 00076 Aalto, Finland.
Physical Review. E
|July 15, 2016
Summary
We developed quantum thermodynamics for systems interacting with modulated heat baths. Quantum coherence prevents reaching Carnot efficiency in quantum heat engines, establishing universal performance bounds.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Physics
Background:
- Understanding quantum systems coupled to external reservoirs is crucial for developing quantum technologies.
- Existing thermodynamic frameworks often struggle with non-equilibrium and modulated conditions.
Purpose of the Study:
- To develop a consistent thermodynamic framework for quantum systems interacting with periodically modulated heat and work reservoirs.
- To derive universal bounds on the efficiency and power of quantum heat engines.
Main Methods:
- Formulation of the first and second laws of thermodynamics by identifying affinities and fluxes.
- Analysis within the linear response regime, expressing entropy production as a quadratic form in affinities.
- Specialization to Lindblad dynamics to identify kinetic coefficients using correlation functions.
Main Results:
- Consistent formulation of thermodynamic laws for modulated quantum systems.
- Identification of kinetic coefficients and derivation of reciprocity relations.
- Discovery of universal bounds on quantum heat engine efficiency and power, showing Carnot efficiency is unattainable with quantum coherence.
Conclusions:
- The developed framework provides a powerful tool for analyzing non-equilibrium quantum thermodynamics.
- Quantum coherence fundamentally limits the efficiency of quantum heat engines.
- The findings have implications for the design and optimization of quantum devices.
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