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arXiv · 1904.12128

Achieve Higher Efficiency at Maximum Power with Finite-time Quantum Otto Cycle

Jin-Fu Chen·Chang-Pu Sun·Hui Dong
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Abstract

The optimization of finite-time thermodynamic heat engines was intensively explored recently, yet limited to few cycles, e.g. finite-time Carnot-like cycle. In this paper, we supplement a new type of finite-time engine with quantum Otto cycle and show the better performance. The current model can be widely utilized benefited from the general \mathcal{C}/\tau^{2} scaling of extra work for finite-time adiabatic process with long control time \tau. Such scaling allows analytical optimization of the generic finite-time quantum Otto cycle to surpass the efficiency at maximum power for the Carnot-like engine. We apply the current perturbation method to the quantum piston model and calculate the efficiency at maximum power, which is validated with exact solution.

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Jin-Fu Chen, Chang-Pu Sun, Hui Dong. 2019-04-27. Achieve Higher Efficiency at Maximum Power with Finite-time Quantum Otto Cycle. https://doi.org/10.1103/physreve.100.062140

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