Coherence in the B800 ring of purple bacteria LH2.
We study the quantum coherence in the B800 ring and how it affects the dynamics of excitation energy transfer (EET) in photo-synthetic light-harvesting systems. From an analysis of the spectrum, we determine the disorder parameters for the B800 ring and show that the relatively weak electronic coupling between B800 pigments subtly changes the dynamics of EET and improves the uniformity and robustness of B800 --> B850 EET at room temperature, an example of how a multichromophoric assembly can exploit coherence to optimize the efficiency of photosynthesis. A molecular-level description for the dynamics of EET in the light-harvesting system may prove useful for understanding other nanoscale molecular assemblies and designing efficient nanoscale optical devices.
Department of Chemistry and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Y C
YC
Cheng
R J
RJ
Silbey
D001426:Bacterial Proteins / Q000502:physiology*; D004735:Energy Transfer; D045342:Light-Harvesting Protein Complexes / Q000502:physiology*; D010860:Pigments, Biological / Q000502:physiology*; D011789:Quantum Theory; D012241:Rhodopseudomonas / Q000502:physiology*
C118800:B800-820 light-harvesting complex, Rhodopseudomonas acidophila; D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D010860:Pigments, Biological