We introduce unique class of cyclic quantum thermal machines (QTMs) which can maximize their performance at the finite value of cycle duration $\tau$ where they are most irreversible. These QTMs are based on single-stroke thermodynamic cycles realized by the non-equilibrium steady state (NESS) of the so-called Periodically Refreshed Baths (PReB) process. We find that such QTMs can interpolate between standard collisional QTMs, which consider repeated interactions with single-site environments, and autonomous QTMs operated by simultaneous coupling to multiple macroscopic baths. We discuss the physical realization of such processes and show that their implementation requires a finite number of copies of the baths. Interestingly, maximizing performance by operating in the most irreversible point as a function of $\tau$ comes at the cost of increasing the complexity of realizing such a regime, the latter quantified by the increase in the number of copies of baths required. We demonstrate this physics considering a simple example. We also introduce an elegant description of the PReB process for Gaussian systems in terms of a discrete-time Lyapunov equation. Further, our analysis also reveals interesting connections with Zeno and anti-Zeno effects.

中文翻译：

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定期更新的量子热机

我们介绍了独特的循环量子热机 (QTM) 类别，它们可以在最不可逆的循环持续时间 $\tau$ 的有限值下最大化它们的性能。这些 QTM 基于由所谓的周期性刷新浴 (PReB) 过程的非平衡稳态 (NESS) 实现的单冲程热力学循环。我们发现这样的 QTM 可以在标准碰撞 QTM（考虑与单站点环境的重复交互）和通过同时耦合到多个宏观浴场的自主 QTM 之间进行插值。我们讨论了这些过程的物理实现，并表明它们的实现需要有限数量的浴场副本。有趣的是，通过在作为$\tau$ 的函数的最不可逆点操作来最大化性能是以增加实现这种方案的复杂性为代价的，后者通过所需浴的副本数量的增加来量化。我们通过一个简单的例子来演示这个物理学。我们还根据离散时间 Lyapunov 方程介绍了对高斯系统 PReB 过程的优雅描述。此外，我们的分析还揭示了与芝诺和反芝诺效应的有趣联系。