Abstract:
We investigate the effect of coherence to the excitation transfer
efficiency (ETE) in photosynthetic bacteria Chlorobium tepidum.
We have modelled the monomer of Fenna-Matthews-Olson
(FMO) complex as consisting of eight bacteriochlorophyll-a
sites, while explicitly consider reaction center core complex
(RCC) as an additional site. With the use of realistic bath
spectrum and several dominant vibronic modes in the nonMarkovian master equation, in an effective 9-site model, we
have compared the ETE for an initial pure state and an initial
mixed state. We observe that the initial pure state relaxes
efficiently to increase the trapping at the RCC. We further
illustrate that the coherence play a competitive role to block
the back transfer of excitation from RCC pigment to FMO
complex and hence to maximize the ETE
