Optical cavities hold great promise to manipulate and control the photochemistry of molecules. We demonstrate how molecular photochemical processes can be manipulated by strong light–matter coupling. For a molecule with an inherent conical intersection, optical cavities can induce significant changes in the nonadiabatic dynamics by either splitting the pristine conical intersections into two novel polaritonic conical intersections or by creating light-induced avoided crossings in the polaritonic surfaces. This is demonstrated by exact real-time quantum dynamics simulations of a three-state two-mode model of pyrazine strongly coupled to a single cavity photon mode. We further explore the effects of external environments through dissipative polaritonic dynamics computed using the hierarchical equation of motion method. We find that cavity-controlled photochemistry can be immune to external environments. We also demonstrate that the polariton-induced changes in the dynamics can be monitored by transient absorption spectroscopy.
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This content will become publicly available on July 22, 2025
Dimensional dependence of a molecular-polariton mode number
Vibrational and electronic strong coupling of light with molecular excitations has shown promise for modifying chemical reaction rates. However, the Tavis–Cummings model often used to model such polaritonic chemistry considers only a single discrete cavity mode coupled with the molecular modes, while experimental systems generally consist of a larger number of molecules in cavities with a continuum of modes. Here, we model the polaritonic effects of multimode cavities of arbitrary dimensions and filled with a large number of molecules. We obtain the dependence of the effects on the dimensionality of the cavity, the molecular oscillator strength, and molecular concentration. Combining our model with the transition state theory, we show that polaritonic effects can be altered by a few orders of magnitude compared to including only a single cavity mode, and that the effect is stronger with a larger molecular dipole moment and molecular concentration. However, the change remains negligibly small for realistic chemical systems due to the large number of dark states.
more » « less- Award ID(s):
- 2004287
- NSF-PAR ID:
- 10525644
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 41
- Issue:
- 8
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. C247
- Size(s):
- Article No. C247
- Sponsoring Org:
- National Science Foundation
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