Abstract: Recent evidence suggests that the multiple charge-separation pathways can contribute to photosynthetic performance. In this work, the influence of coupled-dipoles on photosynthetic performance was investigated in a two-charge separation pathways quantum heat engine (QHE) model. And the population dynamics of the two coupled sites, j-V characteristics, and power involving this photosynthetic QHE model were evaluated for the photosynthetic performance. The results illustrate that the photosynthetic performance can be greatly enhanced but quantum interference is deactivated by the coupled-dipoles between the two-charge separation pathways. However, the photosynthetic performance can also be promoted by the deactivated quantum interference owing to the coupled-dipoles. It is a novel role of the coupled-dipoles in the energy transport process of biological photosynthetic, and some artificial strategies may be motivated by this photosynthetic QHE model in the future.

Key words: photosynthetic performance, coupled-dipole, photosynthetic heat engine