Rignon-Bret Antoine, Guarnieri Giacomo, Goold John, Mitchison Mark T
School of Physics, Trinity College Dublin, College Green, Dublin 2, Ireland.
École Normale Supérieure, 45 rue d'Ulm, F-75230 Paris, France.
Phys Rev E. 2021 Jan;103(1-1):012133. doi: 10.1103/PhysRevE.103.012133.
Fluctuations strongly affect the dynamics and functionality of nanoscale thermal machines. Recent developments in stochastic thermodynamics have shown that fluctuations in many far-from-equilibrium systems are constrained by the rate of entropy production via so-called thermodynamic uncertainty relations. These relations imply that increasing the reliability or precision of an engine's power output comes at a greater thermodynamic cost. Here we study the thermodynamics of precision for small thermal machines in the quantum regime. In particular, we derive exact relations between the power, power fluctuations, and entropy production rate for several models of few-qubit engines (both autonomous and cyclic) that perform work on a quantized load. Depending on the context, we find that quantum coherence can either help or hinder where power fluctuations are concerned. We discuss design principles for reducing such fluctuations in quantum nanomachines and propose an autonomous three-qubit engine whose power output for a given entropy production is more reliable than would be allowed by any classical Markovian model.
涨落强烈影响纳米级热机的动力学和功能。随机热力学的最新进展表明，许多远离平衡系统中的涨落受到通过所谓热力学不确定性关系的熵产生率的限制。这些关系意味着提高发动机功率输出的可靠性或精度会带来更高的热力学成本。在这里，我们研究量子 regime 中小热机的精度热力学。特别是，我们推导了几种对量子化负载做功的少量子比特发动机（包括自主和循环）模型的功率、功率涨落和熵产生率之间的精确关系。根据具体情况，我们发现量子相干在功率涨落方面既可能有帮助也可能有阻碍。我们讨论了减少量子纳米机器中此类涨落的设计原则，并提出了一种自主三量子比特发动机，其在给定熵产生下的功率输出比任何经典马尔可夫模型所允许的更可靠。
