Clustered Geometries Exploiting Quantum Coherence Effects for Efficient Energy Transfer in Light Harvesting

TL;DR

This paper investigates how quantum coherence and geometric arrangements in light-harvesting systems enhance energy transfer efficiency, revealing new design principles that outperform classical theories and can guide future material development.

Contribution

It demonstrates that dimerized geometries with quantum coherence significantly improve energy transfer efficiency, providing a novel framework for designing advanced light-harvesting systems.

Findings

Dimerized geometries exhibit enhanced coherence and efficiency.

Quantum coherence enables energy tuning beyond classical predictions.

Clustered networks facilitate rapid energy relaxation and transfer.

Abstract

Elucidating quantum coherence effects and geometrical factors for efficient energy transfer in photosynthesis has the potential to uncover non-classical design principles for advanced organic materials. We study energy transfer in a linear light-harvesting model to reveal that dimerized geometries with strong electronic coherences within donor and acceptor pairs exhibit significantly improved efficiency, which is in marked contrast to predictions of the classical F\"orster theory. We reveal that energy tuning due to coherent delocalization of photoexcitations is mainly responsible for the efficiency optimization. This coherence-assisted energy-tuning mechanism also explains the energetics and chlorophyll arrangements in the widely-studied Fenna-Matthews-Olson complex. We argue that a clustered network with rapid energy relaxation among donors and resonant energy transfer from donor to acceptor states provides a basic formula for constructing efficient light-harvesting systems, and the general principles revealed here can be generalized to larger systems and benefit future innovation of efficient molecular light-harvesting materials.