Non-Markovianity in photosynthetic reaction centers: a noise-induced quantum coherence perspective

Abstract

The long-standing problem of nearly perfect photosynthetic yield in some types of bacteria and nearly all kinds of plants despite the interaction with a hot and noisy environment has witnessed quantum optical explanations in the last decade. Typically in these explanations, photosynthetic reaction centers are modeled as five-level quantum heat engines where the generation of Fano-type interference due to the coupling of discrete state transitions with a common Markovian reservoir is held responsible for the enhancement of the photosynthetic efficiency. In this work, we go beyond the Born-Markov approximation used in the earlier works and study the impact of non-Markovian environments with Lorentzian spectral densities on the dynamics of light-harvesting complexes. As the main result of this work we find that irrespective of our choice of parameters falling in the over-, under-, and critically damped regimes, the non-Markovian effects can increase noise-induced coherence as compared to the corresponding Markovian case under the transient time conditions.