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arXiv · 2606.19287

Suppression of ionization stabilization in a driven Morse-Soft-Coulomb system

Murilo D. Forlevesi·Emanuel Fernandes de Lima·Gabriel Albertin Amici
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Abstract

Ionization stabilization is a well-known phenomenon in strongly driven Soft-Coulomb atomic models, where the ionization probability decrease as the field amplitude increases. In this work, we investigate how this process is affected by introducing a repulsive Morse barrier into the binding potential, leading to the Morse-Soft-Coulomb (MsC) model. A systematic comparison between the Soft-Coulomb and Morse-Soft-Coulomb systems is performed for different values of the softening parameter. Ionization probabilities, escape-time and Lagrangian descriptor maps reveal that the stabilization observed in the Soft-Coulomb model is suppressed in the Morse-Soft-Coulomb system. To elucidate the origin of this behavior, we analyze the corresponding Kramers-Henneberger effective potentials. While the Soft-Coulomb model develops a symmetric double-well structure supporting a large trapping region, the Morse-Soft-Coulomb potential exhibits a single effective minimum with a significative smaller trapping region. Our result indicate that the repulsive barrier leads to the suppression of the ionization stabilization.

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Murilo D. Forlevesi, Emanuel Fernandes de Lima, Gabriel Albertin Amici. 2026-08-17. Suppression of ionization stabilization in a driven Morse-Soft-Coulomb system. https://arxiv.org/abs/2606.19287

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