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Published on: August 1, 2017
Enhancing quantum heat engine performance via unitary-enabled exponential speedup of thermalization
Dehua Liu1,2, Jianhui Wang2
1Hubei Normal University, College of Physics and Electronic Science, Huangshi 435002, China.
Physical Review. E
|May 16, 2026
Summary
This study introduces a modified quantum heat engine that uses a unitary operation to accelerate thermalization, significantly boosting power and efficiency compared to standard quantum engines.
Area of Science:
- Quantum thermodynamics
- Open quantum systems
- Quantum heat engines
Background:
- Standard quantum Otto cycle limitations
- Open-system dynamics and thermalization
- Enhancing quantum engine performance
Purpose of the Study:
- Investigate a finite-time quantum Otto-like heat engine
- Introduce a unitary operation to accelerate thermalization
- Analyze performance enhancement over standard cycles
Main Methods:
- Single-qubit working substance
- Finite-time quantum Otto-like cycle with unitary operation
- Derivation of analytic expressions for work, heat, and efficiency
- Numerical simulations and comparative analysis
Main Results:
- Unitary operation suppresses slow decay modes and broadens spectral gap
- Accelerated thermalization process toward stationarity
- Significant boost in power and efficiency with appropriate parameter selection
- Modified cycle outperforms conventional and shortcut to adiabatic protocols
Conclusions:
- The proposed Otto-like engine with a unitary operation offers superior performance
- The unitary operation is key to enhancing power and efficiency
- This modified cycle represents a promising advancement in quantum heat engine design
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