Interacting Rydberg Exciton-Polaritons in Two-Dimensional Transition Metal Dichalcogenides

Strong optical nonlinearities play a central role in realizing quantum photonic technologies. In solid state systems, the exciton-polariton which result from the hybridization of material excitations and cavity photons are an attractive candidate to realize such nonlinearities. The interaction arising from the material component, excitons, forms the basis of the polaritonic nonlinearity. Several solid state systems have demonstrated nonlinear interaction of polaritons using the n = 1 excitonic state. However, the nonlinear interaction can be significantly enhanced if excited Rydberg excitonic states can be used instead of the ground state excitons. Recently such excited Rydberg excitonic states have been observed in monolayer transition metal dichalcogenides. Here we demonstrate the formation of Rydberg exciton-polaritons in monolayer WSe2 embedded in a microcavity. Owing to the larger wavefunctions of the Rydberg excitons, these polaritons show greater nonlinear response evidenced through the blue shift of the lower polariton branch under optical excitation. The demonstration of Rydberg exciton-polaritons in two-dimensional semiconductors and their enhanced nonlinear response may facilitate the realization of quantum photonic logic gates and processors.