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Before Förster. Initial excitation in photosynthetic light harvesting.

Karki, Khadga Jung LU ; Chen, Junsheng LU ; Sakurai, Atsunori ; Shi, Qi LU ; Gardiner, A. ; Kuhn, O ; Cogdell, Richard J and Pullerits, Tönu LU (2019) In Chemical Science 10. p.7923-7928
Abstract
Electronic 2D spectroscopy allows nontrivial quantum effects to be explored in unprecedented detail. Here, we apply recently developed fluorescence detected coherent 2D spectroscopy to study the light harvesting antenna 2 (LH2) of photosynthetic purple bacteria. We report double quantum coherence 2D spectra which show clear cross peaks indicating correlated excitations. Similar results are found for rephasing and nonrephasing signals. Analysis of signal generating quantum pathways leads to the conclusion that, contrary to the currently prevailing physical picture, the two weakly coupled pigment rings of LH2 share the initial electronic excitation leading to quantum mechanical correlation between the two clearly separate absorption bands.... (More)
Electronic 2D spectroscopy allows nontrivial quantum effects to be explored in unprecedented detail. Here, we apply recently developed fluorescence detected coherent 2D spectroscopy to study the light harvesting antenna 2 (LH2) of photosynthetic purple bacteria. We report double quantum coherence 2D spectra which show clear cross peaks indicating correlated excitations. Similar results are found for rephasing and nonrephasing signals. Analysis of signal generating quantum pathways leads to the conclusion that, contrary to the currently prevailing physical picture, the two weakly coupled pigment rings of LH2 share the initial electronic excitation leading to quantum mechanical correlation between the two clearly separate absorption bands. These results are general and have consequences for the interpretation of initially created excited states not only in photosynthesis but in all light absorbing systems composed of weakly interacting pigments where the excitation transfer is commonly described by using Förster theory. Being able to spectrally resolve the nonequilibrium dynamics immediately following photoabsorption may provide a glimpse to the systems' transition into the Förster regime. (Less)
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organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Chemical Science
volume
10
pages
7923 - 7928
publisher
Royal Society of Chemistry
ISSN
2041-6539
DOI
10.1039/C9SC01888C
language
English
LU publication?
yes
id
79d6c7b4-5024-45a5-9fcf-a0f5465a08ba
date added to LUP
2019-09-14 13:45:19
date last changed
2020-12-13 04:14:03
@article{79d6c7b4-5024-45a5-9fcf-a0f5465a08ba,
  abstract     = {Electronic 2D spectroscopy allows nontrivial quantum effects to be explored in unprecedented detail. Here, we apply recently developed fluorescence detected coherent 2D spectroscopy to study the light harvesting antenna 2 (LH2) of photosynthetic purple bacteria. We report double quantum coherence 2D spectra which show clear cross peaks indicating correlated excitations. Similar results are found for rephasing and nonrephasing signals. Analysis of signal generating quantum pathways leads to the conclusion that, contrary to the currently prevailing physical picture, the two weakly coupled pigment rings of LH2 share the initial electronic excitation leading to quantum mechanical correlation between the two clearly separate absorption bands. These results are general and have consequences for the interpretation of initially created excited states not only in photosynthesis but in all light absorbing systems composed of weakly interacting pigments where the excitation transfer is commonly described by using Förster theory. Being able to spectrally resolve the nonequilibrium dynamics immediately following photoabsorption may provide a glimpse to the systems' transition into the Förster regime.},
  author       = {Karki, Khadga Jung and Chen, Junsheng and Sakurai, Atsunori and Shi, Qi and Gardiner, A. and Kuhn, O and Cogdell, Richard J and Pullerits, Tönu},
  issn         = {2041-6539},
  language     = {eng},
  pages        = {7923--7928},
  publisher    = {Royal Society of Chemistry},
  series       = {Chemical Science},
  title        = {Before Förster. Initial excitation in photosynthetic light harvesting.},
  url          = {http://dx.doi.org/10.1039/C9SC01888C},
  doi          = {10.1039/C9SC01888C},
  volume       = {10},
  year         = {2019},
}