Speaker
Description
The traditional Förster theory applies in the limit where the intermolecular coupling is weak, and the system-bath coupling is strong. We use an approximation for the bath to generalize the traditional Förster master equation for the state population probabilities into a complete master equation for the system's reduced statistical operator. The bath ansatz comes from a zero-th order perturbation in the system-system coupling. It allows us to formulate the weak intramolecular coupling Förster resonance energy transfer theory in a form suitable for calculating ultrafast nonlinear response of molecular systems.
The theory predicts a rapid initial coherent evolution of populations arising from a transient initial coherence-dependent term, which induces a slippage of the initial condition that persists during subsequent rate-controlled transfer. Comparison with exact numerical results (HEOM) confirms the clear improvement of the present generalization over earlier formulations of the Förster theory and delineates its range of validity.
Reference:
Förster resonance energy transfer with transient coherent effects, Maximilian Meyer-Mölleringhof, Pablo Martinez-Azcona, Aurélia Chenu, Tomáš Mančal, https://arxiv.org/abs/2602.17789