Session: Physical Chemistry Poster:

Molecular polaritons in the infrared regime at strong and ultra-strong light-matter interaction is an exciting and recent research topic to control chemical reactions and light emission. By solving the time-dependent Schrödinger equation, we compare the photodissociation dynamics of a single hydrogen fluoride (HF) molecule in its ground electronic state, subject to driving either by a strong cw infrared laser or by a single-mode infrared cavity vacuum. In absence of additional external sources, a polar molecular mode prepared in its ground vibrational level can be dissociated when is coupled to a quantized field mode in the vacuum state. In the ultra-strong coupling regime, numerical simulations with the Multi-level quantum Rabi model reveal dissociation probabilities of up to 20% in sub-picoseconds scale for the HF molecule. In contrast, cw infrared laser with intensities not smaller than 10¹⁴W/cm²are required to obtain similar dissociation rates in free space. We point out that self-dissociation probabilities are possible due to polar nature of molecular mode that induces cavity field displacements and depend on the initial conditions, which are prepared by a non-adiabatic evolution. In addition, we also propose an experiment in which both molecular fragments and photons generated in the polaritonic system can be detected at the same time without any other external force or pump-probe detection schemes. Our work highlights new unexpected processes in chemical reactions for molecules immersed in quantized fields, in comparison with works in cavity-free scenarios that only involved laser pulses.

Felipe Herrera

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