Collective polaritonic effects on chemical dynamics suppressed by disorder

We present a powerful formalism, disordered collective dynamics using truncated equations (d-CUT-E), to simulate the ultrafast quantum dynamics of molecular polaritons in the collective strong coupling regime, where a disordered ensemble of N≫106 molecules couples to a cavity mode. Notably, we can capture this dynamics with a cavity hosting a single molecule with ∼Nbins electronic states, where Nbins≪N is the number of bins discretizing the disorder distribution. Using d-CUT-E we conclude that strong coupling, as evaluated from linear optical spectra, can be a poor proxy for polariton chemistry. For highly disordered ensembles, total reaction yield upon broadband excitation is identical to that outside of the cavity, while narrowband excitation produces distinct reaction yields solely due to differences in the initial states prepared prior to the reaction. Published by the American Physical Society 2024