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Impurity reveals distinct operational phases in quantum thermodynamic cycles
Aditya Prakash1, Abhishek Kumar1, Colin Benjamin1
1School of Physical Sciences, National Institute of Science Education & Research, Jatni-752050, India and Homi Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, India.
Physical Review. E
|December 23, 2022
Summary
Adding an impurity to quantum heat cycles, like the quantum Otto cycle, can unlock new operating modes and even achieve Carnot efficiency. This impurity significantly impacts quantum refrigerators and cold pumps.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Condensed matter physics
Background:
- Quantum heat cycles are theoretical models for energy conversion at the quantum level.
- The behavior of quantum systems can be significantly altered by external factors like impurities.
Purpose of the Study:
- To investigate the impact of impurities on quantum Otto and Carnot heat cycles.
- To explore the emergence of new operational phases due to impurities.
Main Methods:
- Modeling quantum heat cycles using a single quantum particle in an infinite square well potential.
- Applying perturbative methods to analyze the effects of impurities in strong- and weak-coupling regimes.
- Deriving analytical expressions for work and efficiency.
Main Results:
- An embedded impurity introduces new operational phases: quantum heat engine, quantum refrigerator, and quantum cold pump.
- The efficiency of the quantum Otto heat engine can reach Carnot efficiency under specific conditions.
- Impurity presence non-trivially affects the cooling power and coefficient of performance.
Conclusions:
- Impurities are crucial for understanding and manipulating quantum thermodynamic cycles.
- The study reveals novel quantum phenomena and potential applications in quantum refrigeration and energy conversion.
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