Photoprotecting uracil by coupling with lossy nanocavities

TL;DR

This paper demonstrates that coupling uracil with lossy nanocavities can significantly accelerate its photorelaxation, providing a novel approach to photoprotection by optimizing light-matter interactions and cavity dissipation effects.

Contribution

It introduces a theoretical framework showing how strong coupling with lossy nanocavities can enhance uracil's photorelaxation rate, challenging the idea that higher quality factors always improve performance.

Findings

Optimal trade-off between coupling strength and photon decay maximizes relaxation speed.

Lossy nanocavities can outperform high-Q cavities in photoprotection.

Speedup achievable with simple nanosphere pseudomodes.

Abstract

We analyze how the photorelaxation dynamics of a molecule can be controlled by modifying its electromagnetic environment using a nanocavity mode. In particular, we consider the photorelaxation of the RNA nucleobase uracil, which is the natural mechanism to prevent photodamage. In our theoretical work, we identify the operative conditions in which strong coupling with the cavity mode can open an efficient photoprotective channel, resulting in a relaxation dynamics twice as fast than the natural one. We rely on a state-of-the-art chemically-detailed molecular model and a non-Hermitian Hamiltonian propagation approach to perform full-quantum simulations of the system dissipative dynamics. By focusing on the photon decay, our analysis unveils the active role played by cavity-induced dissipative processes in modifying chemical reaction rates, in the context of molecular polaritonics. Remarkably, we find that the photorelaxation efficiency is maximized when an optimal trade-off between light-matter coupling strength and photon decay rate is satisfied. This result is in contrast with the common intuition that increasing the quality factor of nanocavities and plasmonic devices improves their performance. Finally, we use a detailed model of a metal nanoparticle to show that the speedup of the uracil relaxation could be observed via coupling with a nanosphere pseudomode, without requiring the implementation of complex nanophotonic structures.