Photosynthetic reaction center as a quantum heat engine

@article{Dorfman2013PhotosyntheticRC,
  title={Photosynthetic reaction center as a quantum heat engine},
  author={Konstantin E. Dorfman and Dmitri V. Voronine and Shaul Mukamel and Marlan O. Scully},
  journal={Proceedings of the National Academy of Sciences},
  year={2013},
  volume={110},
  pages={2746 - 2751}
}
Two seemingly unrelated effects attributed to quantum coherence have been reported recently in natural and artificial light-harvesting systems. First, an enhanced solar cell efficiency was predicted and second, population oscillations were measured in photosynthetic antennae excited by sequences of coherent ultrashort laser pulses. Because both systems operate as quantum heat engines (QHEs) that convert the solar photon energy to useful work (electric currents or chemical energy, respectively… 

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References

SHOWING 1-10 OF 64 REFERENCES
Direct evidence of quantum transport in photosynthetic light-harvesting complexes
TLDR
Experimental evidence is provided that interaction between the bacteriochlorophyll chromophores and the protein environment surrounding them not only prolongs quantum coherence, but also spawns reversible, oscillatory energy transfer among excited states.
Long-lived quantum coherence in photosynthetic complexes at physiological temperature
TLDR
Evidence that quantum coherence survives in FMO at physiological temperature for at least 300 fs, long enough to impact biological energy transport is presented, proving that the wave-like energy transfer process discovered at 77 K is directly relevant to biological function.
Quantum oscillatory exciton migration in photosynthetic reaction centers.
TLDR
Simulation of the photosynthetic reaction center of photosystem II clearly establish oscillatory energy transport at room temperature originating from interference of quantum pathways, and signatures of quantum transport may be observed by two dimensional coherent optical spectroscopy.
Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems
TLDR
Previous two-dimensional electronic spectroscopy investigations of the FMO bacteriochlorophyll complex are extended, and direct evidence is obtained for remarkably long-lived electronic quantum coherence playing an important part in energy transfer processes within this system is obtained.
Quantum coherence spectroscopy reveals complex dynamics in bacterial light-harvesting complex 2 (LH2)
  • E. HarelG. Engel
  • Physics, Chemistry
    Proceedings of the National Academy of Sciences
  • 2012
TLDR
This work provides experimental evidence of long-lived quantum coherence between the spectrally separated B800 and B850 rings of the light-harvesting complex 2 (LH2) of purple bacteria and suggests that quantum mechanical interference between different energy transfer pathways may be important even at ambient temperature.
Coherently wired light-harvesting in photosynthetic marine algae at ambient temperature
TLDR
Observations provide compelling evidence for quantum-coherent sharing of electronic excitation across the 5-nm-wide proteins under biologically relevant conditions, suggesting that distant molecules within the photosynthetic proteins are ‘wired’ together by quantum coherence for more efficient light-harvesting in cryptophyte marine algae.
Theoretical examination of quantum coherence in a photosynthetic system at physiological temperature
TLDR
The numerical results reveal that quantum wave-like motion persists for several hundred femtoseconds even at physiological temperature, and suggest that the FMO complex may work as a rectifier for unidirectional energy flow from the peripheral light-harvesting antenna to the reaction center complex by taking advantage of quantum coherence and the energy landscape of pigments tuned by the protein scaffold.
Elucidation of the timescales and origins of quantum electronic coherence in LHCII.
TLDR
This work presents a new, direct method to access coherence signals: a coherence-specific polarization sequence, which isolates the excitonic coherence features from the population signals that usually dominate two-dimensional spectra and elucidate coherent dynamics.
Highly efficient energy excitation transfer in light-harvesting complexes: The fundamental role of n
TLDR
This work identifies key mechanisms through which noise such as dephasing, perhaps counter intuitively, may actually aid transport through a dissipative network by opening up additional pathways for excitation transfer.
Quantum heat engine power can be increased by noise-induced coherence
TLDR
Noise-induced coherence enables us to break detailed balance and get more power out of a laser or photocell QHE, and this coherence can be induced by the same noisy (thermal) emission and absorption processes that drive the QHE.
...
...