Excitation energy transfer efficiency: equivalence of transient and stationary setting and the absence of non-Markovian effects

TL;DR

This paper demonstrates that excitation energy transfer efficiency in photosynthetic complexes is essentially the same in transient and stationary settings and is unaffected by non-Markovian effects, with classical rate equations providing equivalent results.

Contribution

It establishes the equivalence of transient and stationary efficiency calculations and shows non-Markovianity does not influence the efficiency, bridging quantum and classical descriptions.

Findings

Transient and stationary efficiencies are nearly identical.

Non-Markovian effects do not alter efficiency.

Classical rate equations yield the same efficiency as quantum models.

Abstract

We analyze efficiency of excitation energy transfer in photosynthetic complexes in transient and stationary setting. In the transient setting the absorption process is modeled as an individual event resulting in a subsequent relaxation dynamics. In the stationary setting the absorption is a continuous stationary process, leading to the nonequilibrium steady state. We show that, as far as the efficiency is concerned, both settings can be considered to be the same, as they result in almost identical efficiency. We also show that non-Markovianity has no effect on the resulting efficiency, i.e., corresponding Markovian dynamics results in identical efficiency. Even more, if one maps dynamics to appropriate classical rate equations, the same efficiency as in quantum case is obtained.