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Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
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Impact of Vibrational Coherence on the Quantum Yield at a Conical Intersection
Hong-Guang Duan1,2,3, R J Dwayne Miller2,3,4, Michael Thorwart1,3
1I. Institut für Theoretische Physik, Universität Hamburg , Jungiusstraße 9, 20355 Hamburg, Germany.
The Journal of Physical Chemistry Letters
|August 23, 2016
Summary
Vibrational coherence significantly impacts quantum dynamics near conical intersections. Less coherent wave packets move faster but yield less, showing complex relaxation pathways and Stueckelberg oscillations.
Area of Science:
- Quantum dynamics
- Chemical physics
- Spectroscopy
Background:
- Conical intersections are crucial for non-adiabatic transitions in molecular systems.
- Vibrational coherence plays a significant role in ultrafast dynamics.
- Understanding these dynamics is key to controlling chemical reactions.
Purpose of the Study:
- To investigate the influence of vibrational coherence on quantum dynamics near a conical intersection.
- To analyze the relaxation pathways and product yields influenced by vibrational coherence.
- To explore interference effects arising from wave packet dynamics.
Main Methods:
- A three-state, two-mode model was employed to simulate quantum dynamics.
- Coherent tuning and coupling modes were transformed into a bath.
- The hierarchy equation of motion (HEOM) approach was used for numerically exact solutions.
- Transient absorption and 2D spectra were calculated.
Main Results:
- Vibrational coherence critically affects wave packet relaxation pathways.
- Reduced vibrational coherence leads to faster traversal of the conical intersection but lower quantum yield.
- Stueckelberg oscillations were observed due to repeated wave packet passages.
Conclusions:
- Vibrational coherence is a key factor governing the outcome of photochemical processes.
- The study provides insights into controlling reaction dynamics through wave packet manipulation.
- The findings highlight the importance of quantum effects in molecular transformations.
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