Hybrid Photonic-Plasmonic Cavities Based on the Nanoparticle-on-a-Mirror Configuration for Large Purcell Factors at Visible Wavelengths

Hybrid plasmonic-photonic cavities are promising structures for enhancing the emission of quantum emitters by increasing the Purcell factor. In this work, we investigate a novel hybrid structure with a nanoparticle-on-a-mirror configuration coupled to a dielectric photonic crystal. This configuration allows to obtain small mode volumes due to the metallic nanoparticle and large Q-factors due to the photonic crystal. We report Purcell factors larger than 105 in the visible spectral region, which are achieved with structures that are experimentally feasible with current technology. We expect that our results may open new avenues for boosting light-matter interactions in nanophotonic systems.