Strong exciton-plasmon coupling in two-dimensional transition metal dichalcogenides*

Two-dimensional transition metal dichalcogenides (2-D TMDs) show promise as photocatalytic materials for water splitting due to their strong light-matter interactions and favorable band gaps and band alignments. Incorporation of plasmonics into these systems is expected to enhance performance due to a variety of effects including large exciton-plasmon coupling.

Here, we show that strong exciton-plasmon coupling is possible in many 2-D TMD systems as evidenced by Rabi splitting in modeled photonic dispersion of thin films of 2-D TMDs coupled to tunable surface plasmons. The results show coupling in every metal-TMD combination between the metals Au, Al, Ag, and Cu and the 2-D TMDs MoS₂, MoSe₂, WS₂, and WSe₂. Finally, we discuss current experimental progress on such systems.