近日，山东工商学院李海团队研究了用相干充电器增强量子电池的力效性：不确定因果顺序的催化作用。相关论文发表在2025年10月30日出版的《物理评论A》杂志上。

近年来，量子电池（QB）模型已成为在量子热力学框架内探索量子效应与能量之间联系的重要平台。

受量子开关（QS）物理实现的启发，研究组在这项工作中提出了一个简单的QB模型，其中一个两级系统作为电池，在一系列相干充电器下，通过引入一个控制量子比特作为QS来执行无限期热序（ICO）充电。在保能碰撞相互作用框架下，分别分析了充电ICO和常规DCO 充电模式下的电池最终充电状态，发现了ICO和DCO充电模式下电池最终充电状态的内在联系。也就是说，ICO带电状态可以理解为DCO带电状态的分裂，伴随着由表征ICO效应的干扰分量所引起的偏移。

这为理解量子电池的功萃取提供了直接理论证据：仅当充电过程中存在量子相干性时，干涉充电效应才能对量子电池的功萃取量（即最大可提取功）产生积极影响，且该效应与电池的平均存储能量无关。通过数值模拟，研究组发现模型中的量子相干性是提升量子电池功萃取量的强大量子资源，而干涉充电效应则发挥类似催化剂的作用，协助量子相干性进一步强化电池的功萃取能力。

此外，研究组还证明增加充电器数量也有助于提升量子电池的最佳功萃取量。最后研究揭示，当相干充电器处于退相干环境中时，干涉充电模式比直接充电模式对退相位噪声具有更强的鲁棒性。该研究深化了人们在量子热力学领域对量子相干性与干涉充电效应的理解。

附：英文原文

Title: Enhancing ergotropy of a quantum battery with coherent chargers: The catalystlike role of indefinite causal order

Author: Hai Li, Haoyuan Ma, Yaming Hao, Wenli Yu

Issue&Volume: 2025/10/30

Abstract: In recent years, quantum battery (QB) models have emerged as crucial platforms for exploring the connections between quantum effects and energy within the framework of quantum thermodynamics. Inspired by the physical implementation of quantum switch (QS), we, in this work, present a simple QB model in which a two-level system as battery, under a series of coherent chargers, performs the indefinite causal order (ICO) charging by introducing a control qubit as QS. Within the energy-preserving collision interaction framework, we analyze the charging ICO and conventional definite causal order (DCO) dynamics, respectively, and discover the underlying connection between the final charged states of battery in ICO and DCO charging modes. That is, the ICO charged state can be understood as a split of the DCO charged state, accompanied by an offset caused by the interference component characterizing the ICO effect. That provides direct theoretical evidence that the ICO effect positively influences the ergotropy (i.e., the maximum extractable work) of QB only when quantum coherence is present in the charging process, and it is independent of the average stored energy of the QB. By combining numerical simulations, we examine that quantum coherence in our model is a strong quantum resource contributing to the ergotropy of QB, while the ICO effect plays a catalyst-like role, assisting quantum coherence in further enhancing the ergotropy of the battery. In addition, we also demonstrate that increasing the number of chargers also benefits the optimal ergotropy of QB. Finally, we reveal that, when the coherent chargers are subject to the dephasing channel, the ICO charging mode is more robust against dephasing noise than the DCO charging mode. This investigation deepens our understanding of quantum coherence and the ICO effect in the context of quantum thermodynamics.

DOI: 10.1103/s6dl-zgkx

Source: https://journals.aps.org/pra/abstract/10.1103/s6dl-zgkx