title: Excitonic and vibrational coherence in artificial photosynthetic systems studied by negative-time ultrafast laser spectroscopy.
abstract: Quantum coherences between excitonic states are believed to have a substantial impact on excitation energy transfer in photosynthetic systems. Here, the excitonic and vibrational coherence relaxation dynamics of artificially synthetic chlorosomes are studied by a sub 7 fs negative-time-delay laser spectroscopy at room temperature. The results provide direct evidence for the quantum coherence of the excitonic dephasing time of 23 ± 1 fs at physiologically relevant temperatures, which is significant in the initial step of energy transfer in chlorosome or chlorosome-like photosynthetic systems. Meanwhile, coherent molecular vibrations in the excited state are also detected without the effect of wave-packet motion in the ground state, which shows that the excited state wave-packet motion contributes greatly to the vibrational modes of ∼150 and ∼1340 cm(-1) in artificial chlorosome systems.
authors.affiliation: State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China. dujuan@mail.siom.ac.cn lengyuxin@mail.siom.ac.cn.
authors.forename: Dongjia
authors.initials: D
authors.lastname: Han
authors.forename: Bing
authors.initials: B
authors.lastname: Xue
authors.forename: Juan
authors.initials: J
authors.lastname: Du
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Miyatake
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tamiaki
authors.forename: Xin
authors.initials: X
authors.lastname: Xing
authors.forename: Wei
authors.initials: W
authors.lastname: Yuan
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Li
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Leng
mesh_terms: D001429:Bacteriochlorophylls / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry; D004735:Energy Transfer; D017785:Photons; D010788:Photosynthesis / Q000502:physiology; D011789:Quantum Theory; D013050:Spectrometry, Fluorescence; D014732:Vibration; D015032:Zinc / Q000737:chemistry
chemical_list: D001429:Bacteriochlorophylls; D056831:Coordination Complexes; D015032:Zinc