2023/12/08 by Raphaël Weber, Susana F. Huelga, Weber, Raphael +3
Engineering · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Quantum Physics (quant-ph) #Thermal Radiation and Cooling Technologies #Thermodynamic and Exergetic Analyses of Power and Cooling Systems
paper · pdf · doi:10.48550/arxiv.2312.05375
openalex publication_date 2023/12/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Quantum heat engines are commonly believed to achieve their optimal efficiency only when operated quasi-statically. When running at finite power, however, they suffer effective friction due to the generation of coherences and transitions between energy eigenstates. It was noted that it is possible to increase the power of a quantum heat engine using external control schemes or suitable dephasing noise. Here, we investigate the thermodynamic cost associated with dephasing noise schemes using both numerical and analytical methods. Our findings unveil that the observed gain in power is generally not free of thermodynamic costs, as it involves energy costs of the control fields or heat flows between thermal and dephasing baths. These contributions must be duly accounted for when determining the engine's overall efficiency. Interestingly, we identify a particular working regime where these costs become negligible, demonstrating that quantum heat engines can be operated at any power with an efficiency per cycle that approaches arbitrarily closely that under quasistatic operation.