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Finite-time performance of a cyclic two-dimensional quantum Ising heat engine
S P Katoorani1, C Kohlfürst1, F Queisser1
1Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328 Dresden, Germany.
Physical Review. E
|August 19, 2025
Summary
This study explores finite-time quantum Otto cycles using an Ising model. Optimal parameters for work and cooling are found, revealing that control work impacts performance and an optimal cycle duration maximizes efficiency.
Area of Science:
- Quantum thermodynamics
- Statistical mechanics
- Condensed matter physics
Background:
- The quantum Otto cycle is a fundamental thermodynamic cycle.
- Understanding finite-time quantum processes is crucial for practical applications.
- Ising models are widely used to study phase transitions and critical phenomena.
Purpose of the Study:
- To investigate the limit cycle regime of a finite-time quantum Otto cycle.
- To determine optimal parameters for work extraction and cooling.
- To analyze the impact of finite-time dynamics and control work on cycle performance.
Main Methods:
- Utilizing Onsager's exact equilibrium solution for a two-dimensional anisotropic Ising model.
- Analyzing the behavior of quantum Otto cycles in both slow and finite-time regimes.
- Quantifying work extraction, cooling, and control work during dissipative strokes.
Main Results:
- Optimal parameters for work extraction and cooling were identified for slow cycles, bypassing phase transitions.
- Finite-time cycles exhibit finite power and cooling currents.
- Control work significantly affects performance in finite-time cycles, necessitating an optimal cycle duration for maximum efficiency.
Conclusions:
- Finite-time quantum Otto cycles require careful consideration of control work, which can be substantial.
- An optimal cycle duration exists to balance power/cooling and control work.
- Net-zero-energy transitions can lead to unintended reservoir heating, impacting overall efficiency.
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