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Finite-time performance of a quantum heat engine with a squeezed thermal bath
Jianhui Wang1,2, Jizhou He1, Yongli Ma2
1Department of Physics, Nanchang University, Nanchang 330031, China.
Physical Review. E
|December 25, 2019
Summary
This study analyzes a quantum Otto engine using squeezed states, finding that squeezing enhances engine efficiency. However, this enhancement comes with significantly increased power fluctuations.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Quantum optics
Background:
- Quantum Otto engines are theoretical models for quantum heat engines.
- Squeezed states of light offer unique quantum properties.
- Finite-time thermodynamics considers the performance of engines operating over limited durations.
Purpose of the Study:
- To investigate the finite-time performance of a quantum Otto engine utilizing a hot squeezed bath.
- To derive analytical expressions for work, efficiency, power, and power fluctuations.
- To analyze the impact of squeezing parameters on engine performance.
Main Methods:
- Derivation of analytical expressions for engine performance metrics.
- Optimization of power output with respect to engine frequencies.
- Analysis within the framework of irreversible thermodynamics.
Main Results:
- Analytical formulas for work, efficiency, power, and power fluctuations involving the squeezing parameter.
- Efficiency at maximum power derived, showing dependence on generalized Carnot efficiency.
- Generalized Carnot efficiency shown to be a function of the squeezing parameter.
Conclusions:
- Squeezing enhances the efficiency of the quantum Otto engine.
- Increased power fluctuations are observed as a consequence of squeezing.
- The derived efficiency at maximum power aligns with general forms for nonlinear heat engines.
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