Superradiance Transition and Nonphotochemical Quenching in Photosynthetic Complexes

TL;DR

This study numerically shows that superradiance transitions can significantly influence nonphotochemical quenching in light-harvesting complexes, identifying parameter regions for optimal NPQ performance.

Contribution

It introduces a model linking superradiance transition to NPQ, revealing how electron transfer rates affect energy dissipation in photosynthetic complexes.

Findings

Superradiance transition occurs at specific electron transfer rates.

Superradiance can optimize NPQ efficiency.

Parameter regions for effective superradiance in NPQ identified.

Abstract

We demonstrate numerically that superradiance could play a significant role in nonphotochemical quenching (NPQ) in light-harvesting complexes. Our model consists of a network of five interconnected sites (discrete excitonic states) that are responsible for the NPQ mechanism. Damaging and charge transfer states are linked to their sinks (independent continuum electron spectra), in which the chemical reactions occur. The superradiance transition in the charge transfer (or in the damaging) channel, occurs at particular electron transfer rates from the discrete to the continuum electron spectra, and can be characterized by a segregation of the imaginary parts of the eigenvalues of the effective non-Hermitian Hamiltonian. All five excitonic sites interact with their protein environment that is modeled by a random stochastic process. We find the region of parameters in which the superradiance transition into the charge transfer channel takes place. We demonstrate that this superradiance transition has the capability of producing optimal NPQ performance.