Photoluminescence spectroscopy of hybridized exciton-polariton coupling in silicon nanodisks with nonradiative anapole radiations

TL;DR

This paper investigates strong light-matter coupling in silicon nanodisks with nonradiative anapole states and dye molecules, revealing energy splitting and potential for controlling light scattering at the nanoscale.

Contribution

It demonstrates the emergence of exciton-polariton coupling involving nonradiating anapole states in semiconductor nanodisks, combining numerical, theoretical, and spectroscopic analyses.

Findings

Observation of energy splitting due to strong coupling

Confirmation of spectral responses via photoluminescence spectroscopy

Potential for dynamic tuning of light-matter interactions

Abstract

Semiconductor nanoparticles and nanostructures in the strong coupling regime exhibit an intriguing energy scale in the optical frequencies, which is specified by the Rabi splitting between the upper and lower exciton-polariton states. Technically, exciton-polaritons are part-light, part-matter quasiparticles that arise from the strong interaction of excitonic substances and photonic platforms. In this work, using full-wave numerical and theoretical studies, we showed the emergence of strong light-matter coupling between the nonradiating anapole states from an individual semiconductor nanodisk coupled to a J-aggregate fluorescent dye molecule resonating in the visible spectrum. By demonstrating the physical mechanism behind the observed energy splitting for various Lorentzian linewidth of excitonic material, we theoretically confirmed the obtained spectral responses by conducting photoluminescence spectroscopy analysis. The coupling of anapole resonances in semiconductor nanoparticles with excitonic levels can propose interesting possibilities for the control of directional light scattering in the strong coupling limit, and the dynamic tuning of deep-subwavelength light-matter coupled states by external stimuli.