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arXiv · 2607.15319

Collective Enhancement of Nuclear Excitation for a Nuclear Quantum Battery

Pravin Kumar Dahal·Kieran Hymas·Jack Muir·James Q. Quach
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Abstract

Current implementations of quantum batteries are constrained by limited energy density and short retention times associated with the electronic or molecular excitations. Here we propose a nuclear quantum battery based on collective excitation of the $^{57}$Fe nuclei of density $n$ embedded in a planar hard X-ray waveguide. Using a Green function waveguide-QED description, we study charging via excitation beyond linear response, where saturation and drive back-action reshape the incident pulse. We introduce a self-consistent waveform-engineering protocol that inhibits local radiative decay in the waveguide thus promoting absorption into high-lying collective nuclear excitation manifolds. We show an enhanced excitation cross section of the nuclear ensemble which yields superlinear charging, with maximum studied energy density scaling approximately like $n \sqrt{n}$. Our results provide a route to high-energy-density quantum charging at hard X-ray energies using contemporary X-ray sources and waveguide architectures by identifying nonlinear, collectively enhanced absorption as a key mechanism for nuclear quantum battery operation.

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Pravin Kumar Dahal, Kieran Hymas, Jack Muir, James Q. Quach. 2026-07-16. Collective Enhancement of Nuclear Excitation for a Nuclear Quantum Battery. https://arxiv.org/abs/2607.15319

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