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arXiv · 2510.17605

Harnessing dressed time-dependent density functional theory for the non-perturbative regime: Electron dynamics with double excitations

Dhyey Ray·Anna Baranova·Davood B. Dar·Neepa T. Maitra
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Abstract

Recent progress has been made in capturing spectral features of electronic states of double-excitation character in time-dependent density functional theory (TDDFT) through a frequency-dependent kernel. While it might appear that this development is limited to the perturbative regime, we show that when used within response-reformulated TDDFT, it accurately captures strong-field dynamics involving states of double-excitation character. More generally, this demonstrates how RR-TDDFT enables exchange-correlation functional developments in the response regime, which have so far been more successful than those in the non-linear regime, to be exploited for non-perturbative dynamics, thus significantly broadening their range of applications.

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Dhyey Ray, Anna Baranova, Davood B. Dar, Neepa T. Maitra. 2026-04-16. Harnessing dressed time-dependent density functional theory for the non-perturbative regime: Electron dynamics with double excitations. https://doi.org/10.1103/rvf2-jf13

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