Scalable exciton polariton devices enabled by solution-processed WS 2 inks

Abstract

Atomically thin transition metal dichalcogenides (TMDs) feature robust room-temperature excitons with large binding energies. Through strong coupling with optical cavities, advanced polaritonic devices such as polariton lasers, switches, and transistors have been widely reported. However, the scalability of these TMD-based polaritonic devices remains constrained by micrometer-scale mechanically exfoliated monolayers. Here, we demonstrate large-area scalable exciton polariton devices using electrochemically exfoliated monolayer WS 2 inks. Through interfacial self-assembly, such monolayer WS 2 inks can form densely packed WS 2 films with precise layer-number control. Integrating the WS 2 films with Fabry-Pérot microcavities achieves strong coupling with characteristic anti-crossing dispersions. Crucially, the exciton-photon coupling strength scales linearly with the square root of the layer number, enabled by organic molecular spacers from electrochemical intercalation, which helps to preserve monolayer excitonic properties while enhancing collective oscillator strength. Lithographic patterning further enables spatially confined exciton polaritons. This work establishes a scalable manufacturing platform for 2D-material polaritonics, accelerating their implementation in quantum photonic technologies.