A coherent modified Redfield theory for excitation energy transfer in molecular aggregates

作者：Hwang Fu Yu Hsien; Chen Wei; Cheng Yuan Chung^*

来源：Chemical Physics, 2015, 447: 46-53.

DOI：10.1016/j.chemphys.2014.11.026

• Coherent modified Redfield theory
• Excitation energy transfer
• Light harvesting
• Quantum master equation

Excitation energy transfer (EET) is crucial in photosynthetic light harvesting, and quantum coherence has been recently proven to be a ubiquitous phenomenon in photosynthetic EET. In this work, we derive a coherent modified Redfield theory (CMRT) that generalizes the modified Redfield theory to treat coherence dynamics. We apply the CMRT method to simulate the EET in a dimer system and compare the results with those obtained from numerically exact path integral calculations. The comparison shows that CMRT provides excellent computational efficiency and accuracy within a large EET parameter space. Furthermore, we simulate the EET dynamics in the FMO complex at 77 K using CMRT. The results show pronounced non-Markovian effects and long-lasting coherences in the ultrafast EET, in excellent agreement with calculations using the hierarchy equation of motion approach. In summary, we have successfully developed a simple yet powerful framework for coherent EET dynamics in photosynthetic systems and organic materials.

• 出版日期2015-2-2