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arXiv · 2511.13088

Topological enhancement of a PT-symmetric Su-Schrieffer-Heeger quantum battery

Abstract

We investigate a non-Hermitian quantum battery based on the Su-Schrieffer-Heeger (SSH) lattice, charged through a parity-time (PT)-symmetric protocol that alternates gain and loss between the two sublattices. The interplay between lattice topology and non-Hermiticity gives rise to both bulk and edge exceptional points (EPs), which govern the charging dynamics. In the topological regime, an edge-state EP appears at a smaller gain-loss strength than the bulk thresholds and gives rise to an additional edge-broken regime absent in the trivial configuration. This topology-specific spectral structure is reflected in the charging dynamics, where the topological phase exhibits more favorable transient and long-time performance in the representative non-Hermitian regimes considered here. We further examine the corresponding Lindblad dynamics, identifying the non-Hermitian model as the conditional no-jump description of the same gain-loss processes. The Lindblad results show that the topological advantage remains visible at the level of stored energy, extractable work, and extractable fraction under unconditional open-system evolution. These findings demonstrate that topology constitutes a genuine physical resource for enhancing the performance of quantum batteries.

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A-Long Zhou, Ya-Wen Xiao, Nuo Xu, Li-Li Gao, Long-Jie Li, Hang Zhou, Zi-Min Li, Chuan-Cun Shu. 2026-04-15. Topological enhancement of a PT-symmetric Su-Schrieffer-Heeger quantum battery. https://doi.org/10.1103/4klp-kw27

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