Evolutionary optimization of light-matter coupling in open plasmonic cavities

Abstract

Using a particle swarm optimization algorithm and finite-difference in time-domain simulations, we optimize the coupling strength between excitons in poly(3-hexylthiophene-2,5-diyl) (P3HT) and surface lattice resonances in open cavities defined by arrays of aluminum nanoparticles. Strong light–matter coupling and the formation of exciton-polaritons are demonstrated. Nanoparticle arrays with optimal dimensions have been fabricated and measured, validating the predictions by the numerical method. P3HT is a regioregular semiconducting polymer used as a donor material in acceptor–donor blends for organic photovoltaic applications. Our results demonstrate the efficacy of the proposed method for the optimization of light–matter coupling and its potential application for the enhanced performance of optoelectronic devices.

Molecular Polaritons for Chemistry, Photonics and Quantum Technologies

“…One approach involves a surface plasmon polariton (SPP) generated on a metallic or dielectric surface. − SPPs exhibit a high degree of localization near the surface, making them amenable to coupling with the samples close to the surface, such as a thin film. Brawley et al employed a gold nanodisk structure designed to generate angular dependent surface plasmon mode (Figure a).…”

“…In other words, polariton states inherently exist regardless of photoexcitation. This seemingly unconventional notion stands as a well-established concept in physics, spanning condensed matter physics, − and atomic-molecular optics − (Rydberg polaritons, single atom polaritons, etc.). This concept holds substantial scientific and technical significance, exemplified by achievements like the realization of room temperature polariton condensates, − leveraging polariton propagation to energy or information transfer, − , pushing the boundaries of signal detection thresholds, , and engineering single-photon optical transistors through profound polariton nonlinearity. − …”

Strong light–matter coupling in pentacene thin films on plasmonic arrays

“…[25][26][27][28][29][30] By strong coupling, the energy landscapes of the excited states of organic semiconductors can be modified by the formation of polariton bands at energies higher and lower than the pure exciton energy, which in turn influences the photophysical processes. 31,32 One such process that attracted appreciable interest in the last decade is singlet fission (SF), which describes the spontaneous splitting of one excited singlet exciton into two triplet excitons via a triplet pair state. 33,34 This SF process finds potential application in solar cells due to the duplication of the number of excitons.…”