Real time observations of vibronic interactions between pigments in photosynthetic light-harvesting antennas

2015 Fiscal Year Final Research Report

• Project/Area Number: 25707028
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Condensed matter physics I
• Research Institution: Kumamoto University (2015); Osaka City University
• Principal Investigator: Daisuke Kosumi 熊本大学, パルスパワー科学研究所, 准教授 (70613149)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 超高速分光 / 光物性 / 光合成 / エネルギー伝達 / 非線形分光

Outline of Final Research Achievements

We developed extremely short 5 fs optical pulses and ultrafast coherent spectroscopic techniques to clarify ultrafast energy transfer dynamics of purple bacterial photosynthetic antennas. Quantum beats signals originated from electronic coherence between the B800 and B850 molecular assemblies in photosynthetic antenna LH2 were clearly observed by means of 5 fs coherent spectroscopic measurements. A Fourier analysis of the quantum beats signals shows that multi-modes electronic coherences are formed between B800 and B850. The results suggest that the multi-mode coherences play roles in highly efficient energy transfer of purple bacterial photosynthesis.

Free Research Field

光物性物理学