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Efficiency at maximum power of a quantum heat engine based on two coupled oscillators
Jianhui Wang1,2, Zhuolin Ye1, Yiming Lai1
1Department of Physics, Nanchang University, Nanchang 330031, China.
Summary
This study investigates coupled harmonic oscillators as a quantum heat engine, demonstrating an Otto cycle. The research finds efficiency at maximum power aligns with other systems, offering insights into quantum thermodynamics.
Area of Science:
- Quantum Thermodynamics
- Statistical Mechanics
Background:
- Quantum heat engines offer a pathway to harness thermal energy at the nanoscale.
- Understanding the performance limits of quantum engines is crucial for developing novel energy technologies.
Purpose of the Study:
- To theoretically investigate a system of two coupled harmonic oscillators as a quantum heat engine.
- To analyze the performance of this system operating under an Otto cycle.
Main Methods:
- Theoretical modeling of a two-coupled-oscillator system.
- Analysis of the Otto cycle comprising adiabatic and isochoric processes.
- Application of the semigroup approach to model thermal dynamics during isochoric steps.
Main Results:
- The coupled harmonic oscillator system can be controlled to perform an Otto cycle.
- The upper bound of efficiency at maximum power (EMP) was derived.
- The derived EMP for the coupled system matches that of noninteracting systems.
Conclusions:
- Coupled harmonic oscillators provide a viable model for quantum heat engines.
- The performance limits of this coupled system are consistent with simpler models.
- This work contributes to the understanding of thermodynamic cycles in quantum systems.
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