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arXiv · 2405.08718

Generalized energy gap law: An open system dynamics approach to non-adiabatic phenomena in molecules

N. S. Bassler·M. Reitz·R. Holzinger·A. Vibók·G. J. Halász·B. Gurlek·C. Genes
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Abstract

Non-adiabatic molecular phenomena, arising from the breakdown of the Born-Oppenheimer approximation, govern the fate of virtually all photo-physical and photochemical processes and limit the quantum efficiency of molecules and other solid-state embedded quantum emitters. A simple and elegant description, the energy gap law, was derived five decades ago, predicting that the non-adiabatic coupling between the excited and ground potential landscapes lead to non-radiative decay with a quasi-exponential dependence on the energy gap. We revisit and extend this theory to account for crucial aspects such as vibrational relaxation, dephasing, and radiative loss. We find a closed analytical solution with general validity which indicates a direct proportionality of the non-radiative rate with the vibrational relaxation rate at low temperatures, and with the dephasing rate of the electronic transition at high temperatures. Our work establishes a connection between nanoscale quantum optics, open quantum system dynamics and non-adiabatic molecular physics.

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N. S. Bassler, M. Reitz, R. Holzinger, A. Vibók, G. J. Halász, B. Gurlek, C. Genes. 2024-05-14. Generalized energy gap law: An open system dynamics approach to non-adiabatic phenomena in molecules. https://arxiv.org/abs/2405.08718

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