Photonic molecules via coupled thin-film lithium niobate Fabry–Pérot photonic crystal micro-resonators

We demonstrate a photonic molecule platform based on photonic crystal (PhC) Fabry-Pérot micro-resonators on thin-film lithium niobate, featuring standing-wave resonances confined between PhC mirrors. By adjusting the number of PhC unit cells in the coupling region, we achieve tunable mode splitting, validated by both experimental measurements and numerical simulations. Furthermore, dynamic electro-optic tuning of individual resonators facilitates on-demand mode interaction and hybridization. This offers a compact, single-spatial-mode-guiding architecture with robust dynamic control of photonic molecular interaction for exploring advanced functionalities in integrated nonlinear photonics.