Observation of Coherence in Oygenic Photosynthesis
In photosynthesis, antenna complexes gather light energy and rapidly transfer it to reaction centers where it is converted to stable charge separation. Recent nonlinear spectroscopic experiments have reported long-lived coherences in photosynthetic antenna complexes. Considerable theoretical work has aimed to understand the physical origin of the coherences and their possible role in enhancing energy transfer efficiency. We have recently observed coherent dynamics at 77 K in the photosystem II reaction center (PSII RC) by two-dimensional electronic spectroscopy. I will discuss our observations and speculate about the origin of the coherences and their possible importance for charge separation.