Optimal performance in a chaotic Floquet quantum battery

Lakshmija N K; Uma Divakaran

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arXiv · 2609.35655

Optimal performance in a chaotic Floquet quantum battery

Lakshmija N K·Uma Divakaran

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Abstract

We study a quantum battery consisting of $N$ qubits interacting uniformly with each other. Starting from its ground state, the battery is charged by introducing periodic kicks in the transverse direction along with adding disorder in the interaction direction. Although the battery Hamiltonian along with the initial state preserves the permutation symmetry, the dynamics in presence of disorder during the charging phase takes the system out of the permutation symmetric subspace, resulting to a larger amount of stored energy as compared to that without disorder. In the limit of large disorder, this interplay brings in a possibility of a chaotic charging phase when stored energy can be exactly calculated using random matrix theory. More importantly, we also find that the energy fluctuations decrease and become negligible in the limit of large disorder, which is also when the energy stored is maximum, a condition highly desirable for the optimum functioning of the battery. We complete the battery cycle by considering the storage phase in the presence of dephasing noise. We find that for larger disorder strengths, the ergotropy remains close to the stored energy, indicating nearly complete energy extractability with an efficiency approaching unity.

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Lakshmija N K, Uma Divakaran. 2026-09-28. Optimal performance in a chaotic Floquet quantum battery. https://arxiv.org/abs/2609.35655

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