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arXiv · 2506.21273

Floquet-engineered nondispersive wave packets in helium under combined periodic and static fields

Alejandro González-Melan·John Fitzgerald León Ocampo·Javier Madroñero
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Abstract

We report the numerical observation of two-electron nondispersive wave packets in fully three-dimensional helium subjected to a linearly polarized monochromatic field. These localized quantum states follow periodic trajectories of the classical three-body Coulomb system without dispersion. The system is modeled using a spectral configuration interaction approach based on Coulomb-Sturmian functions, combined with Floquet theory and complex scaling. The resulting quasienergy spectrum reveals the existence of long-lived Floquet states arising from near-resonant coupling between frozen planet configurations.

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Alejandro González-Melan, John Fitzgerald León Ocampo, Javier Madroñero. 2025-06-26. Floquet-engineered nondispersive wave packets in helium under combined periodic and static fields. https://arxiv.org/abs/2506.21273

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