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arXiv · 2512.14999

Trade-off relations and enhancement protocol of quantum battery capacities in multipartite systems

Yiding Wang·Xiaofen Huang·Shao-Ming Fei·Tinggui Zhang
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Abstract

First, we investigate the trade-off relations of quantum battery capacities in two-qubit system. We find that the sum of subsystem battery capacity is governed by the total system capacity, with this trade-off relation persisting for a class of Hamiltonians, including Ising, XX, XXZ and XXX models. Then building on this relation, we define residual battery capacity for general quantum states and establish coherent/incoherent components of subsystem battery capacity. Furthermore, we introduce the protocol to guide the selection of appropriate incoherent unitary operations for enhancing subsystem battery capacity in specific scenarios, along with a sufficient condition for achieving subsystem capacity gain through unitary operation. Numerical examples validate the feasibility of the incoherent operation protocol. Additionally, for the three-qubit system, we also established a set of theories and results parallel to those for two-qubit case. Finally, we determine the minimum time required to enhance subsystem battery capacity via a single incoherent operation in our protocol. Our findings contribute to the development of quantum battery theory and quantum energy storage systems.

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Yiding Wang, Xiaofen Huang, Shao-Ming Fei, Tinggui Zhang. 2025-12-17. Trade-off relations and enhancement protocol of quantum battery capacities in multipartite systems. https://doi.org/10.15302/frontphys.2026.073201

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