Tailoring Exciton-Polariton Emission Lines From Wide-Ranging Monolayer Semiconductors with a Broadband Mie Resonator

Abstract Two-dimensional (2D) exciton-polaritons in monolayer transition metal dichalcogenides (TMDs) exhibit practical advantages in valley coherence, optical nonlinearities, and even bosonic condensation owing to their light emission capability. To achieve robust exciton-polariton emission, strong photon-exciton couplings are required at the TMD monolayer, which is challenging due to its limited thickness. High-quality(Q)-factor optical cavities with narrowband resonances are an effective approach but typically limited to a specific excitonic state of a certain TMD material. Herein, we achieve on-demand exciton-polariton emission for a wide range of monolayer TMDs by hybridizing 2D excitons with broadband Mie resonances spanning the whole visible spectrum. By tightly confining broadband light at the TMD monolayer, our one type of Mie resonator on different TMDs enables enhanced light-matter interactions with multiple excitonic states simultaneously. We demonstrate multi-Rabi splittings and robust polaritonic photoluminescence (PL) in monolayer WSe2, WS2, and MoS2. The hybrid system enables to approach the ultra-strong coupling regime at room temperature.