Emergent mirror symmetry in the optimization of the central-spin quantum battery

Year: 2026

Authors: Yang HY., Zhang K., Wang XH., Shi HL.

Autors Affiliation: Northwest Univ, Sch Phys, Xian 710127, Peoples R China; Shaanxi Key Lab Theoret Phys Frontiers, Xian 710127, Peoples R China; Peng Huanwu Ctr Fundamental Theory, Xian 710127, Peoples R China; Fundamental Discipline Res Ctr Quantum Sci & Techn, Xian 710127, Peoples R China; INO CNR, Largo Enrico Fermi 2, I-50125 Florence, Firenze, Italy; LENS, Largo Enrico Fermi 2, I-50125 Florence, Firenze, Italy.

Abstract: Quantum batteries provide a useful setting for exploring nonequilibrium many-body effects in energy storage. Here we investigate the optimization of a quantum battery based on the central-spin model. We identify two complementary structural indicators associated with the effective charging dynamics: one yields an upper bound on the average charging power, while the other characterizes the buildup of stored energy. We show that these two indicators are jointly optimized at a distinguished initial charger excitation number, which selects a particular Dicke sector of the model. At this common optimal point, the effective charging Hamiltonian becomes exactly mirror symmetric, suggesting mirror symmetry as a useful structural indicator for optimizing the performance of quantum batteries in terms of both charging power and energy storage. We further show that the corresponding optimal dynamics can be closely approximated by product initial states, in particular by spin coherent states whose excitation-number distribution is centered at the symmetry-selected point. Our results establish a direct connection between charging performance, optimal-state structure, and emergent symmetry in the central-spin quantum battery, and suggest symmetry as a useful organizing principle for efficient charging in interacting many-body quantum systems.

Journal/Review: PHYSICAL REVIEW B

Volume: 114 (6)      Pages from: 65402-1  to: 65402-9

More Information: This work was supported by the NSFC (Grants No. 12275215, No. 12305028, and No. 12247103), and the Youth Innovation Team of Shaanxi Universities. K.Z. is supported by the China Postdoctoral Science Foundation under Grant No. 2025M773421, Shaanxi Province Postdoctoral Science Foundation under Grant No. 2025BSHYDZZ017, and Scientific Research Program Funded by Education Department of Shaanxi Provincial Government (Program No. 24JP186). H.L.S. was supported by the European Commission through the H2020 QuantERA ERA-NET Cofund in Quantum Technologies project MENTA and received funding under Horizon Europe programme HORIZONCL4-2022-QUANTUM-02-SGA via Project No. 101113690 (PASQuanS2.1).
KeyWords: Coherent Dynamics
DOI: 10.1103/sr8x-x2kr