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arXiv · 2404.14505

Reformulation of Time-Dependent Density Functional Theory for Non-Perturbative Dynamics: The Rabi Oscillation Problem Resolved

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

Rabi oscillations have long been thought to be out of reach in simulations using time-dependent density functional theory (TDDFT), a prominent symptom of the failure of the adiabatic approximation for non-perturbative dynamics. We present a reformulation of TDDFT which requires response quantities only, thus enabling an adiabatic approximation to predict such dynamics accurately because the functional is evaluated on a density close to the ground-state, instead of on the fully non-perturbative density. Our reformulation applies to it any real-time dynamics, redeeming TDDFT far from equilibrium. Examples of a resonantly-driven local excitation in a model He atom, and charge-transfer in the LiCN molecule are given.

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Davood B. Dar, Anna Baranova, Neepa T. Maitra. 2024-04-22. Reformulation of Time-Dependent Density Functional Theory for Non-Perturbative Dynamics: The Rabi Oscillation Problem Resolved. https://arxiv.org/abs/2404.14505

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