Quantum control of internal conversion in 24-vibrational-mode pyrazine

<div> <div> <div> <p>The rational control of non-radiative relaxation remains an unfulfilled goal for synthetic chemistry. In this study, we show strongly coupling an ensemble of molecules to the virtual photons of an electromagnetic cavity provides a rational handle over ultrafast, non-radiative dynamics. Specifically, we control the concentration of zinc tetraphenyl porphyrin molecules within nano-scale Fabry-Perot cavity structures to show a variable collective vacuum Rabi splitting between the polaritons coincides with changes in internal conversion rates. We find these changes obey a power law dependence on the collective vacuum Rabi splitting, but de- viate from the predictions of so-called gap laws. We also show simple theories of structural changes caused by polariton formation cannot explain discrepancies between our results and established theoretical predictions. Our results demonstrate a mechanism by which cavity polariton formation controls the fundamental photo-physics of light harvesting and photo- catalytic molecular moieties and the gap remaining in our fundamental understanding of these mechanisms. </p> </div> </div> </div>

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Quantum Control of Ultrafast Internal Conversion using Nano-Confined Virtual Photons

10.26434/chemrxiv.11164796.v1 ◽

2019 ◽

Author(s):

Aleksandr Avramenko ◽

Aaron Rury

Keyword(s):

Quantum Control ◽

Internal Conversion ◽

Structural Changes ◽

Radiative Relaxation ◽

Rabi Splitting ◽

Conversion Rates ◽

Tetraphenyl Porphyrin ◽

Virtual Photons ◽

Theoretical Predictions ◽

Vacuum Rabi Splitting

<div> <div> <div> <p>The rational control of non-radiative relaxation remains an unfulfilled goal for synthetic chemistry. In this study, we show strongly coupling an ensemble of molecules to the virtual photons of an electromagnetic cavity provides a rational handle over ultrafast, non-radiative dynamics. Specifically, we control the concentration of zinc tetraphenyl porphyrin molecules within nano-scale Fabry-Perot cavity structures to show a variable collective vacuum Rabi splitting between the polaritons coincides with changes in internal conversion rates. We find these changes obey a power law dependence on the collective vacuum Rabi splitting, but de- viate from the predictions of so-called gap laws. We also show simple theories of structural changes caused by polariton formation cannot explain discrepancies between our results and established theoretical predictions. Our results demonstrate a mechanism by which cavity polariton formation controls the fundamental photo-physics of light harvesting and photo- catalytic molecular moieties and the gap remaining in our fundamental understanding of these mechanisms. </p> </div> </div> </div>

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Femtosecond stimulated Raman spectroscopy of the dark S1 excited state of carotenoid in photosynthetic light harvesting complex.

Acta Biochimica Polonica ◽

10.18388/abp.2012_2169 ◽

2012 ◽

Vol 59 (1) ◽

Cited By ~ 6

Author(s):

Masayuki Yoshizawa ◽

Ryosuke Nakamura ◽

Orihiro Yoshimatsu ◽

Kenta Abe ◽

Shunsuke Sakai ◽

...

Keyword(s):

Raman Spectroscopy ◽

Excited State ◽

High Frequency ◽

Internal Conversion ◽

Light Harvesting ◽

Vibrational Mode ◽

Vibrational Dynamics ◽

Light Harvesting Complex ◽

High Frequency Shift ◽

Stimulated Raman

Vibrational dynamics of the excited state in the light-harvesting complex (LH1) have been investigated by femtosecond stimulated Raman spectroscopy (FSRS). The native and reconstituted LH1 complexes have same dynamics. The ν(1) (C=C stretching) vibrational mode of spirilloxanthin in LH1 shows ultrafast high-frequency shift in the S(1) excited state with a time constant of 0.3 ps. It is assigned to the vibrational relaxation of the S(1) state following the internal conversion from the photoexcited S(2) state.

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