Room-temperature Tamm-plasmon exciton-polaritons with a WSe2 monolayer.

TLDR: A Tamm-plasmon-polariton structure is implemented and the coupling to a monolayer of WSe2, hosting highly stable excitons is studied, featuring an anti-crossing between the exciton and photon modes with a Rabi-splitting of 23.5 meV.

Abstract: Solid-state cavity quantum electrodynamics is a rapidly advancing field, which explores the frontiers of light–matter coupling. Metal-based approaches are of particular interest in this field, as they carry the potential to squeeze optical modes to spaces significantly below the diffraction limit. Transition metal dichalcogenides are ideally suited as the active material in cavity quantum electrodynamics, as they interact strongly with light at the ultimate monolayer limit. Here, we implement a Tamm-plasmon-polariton structure and study the coupling to a monolayer of WSe2, hosting highly stable excitons. Exciton-polariton formation at room temperature is manifested in the characteristic energy–momentum dispersion relation studied in photoluminescence, featuring an anti-crossing between the exciton and photon modes with a Rabi-splitting of 23.5 meV. Creating polaritonic quasiparticles in monolithic, compact architectures with atomic monolayers under ambient conditions is a crucial step towards the exploration of nonlinearities, macroscopic coherence and advanced spinor physics with novel, low-mass bosons. Thanks to their strong light-matter interaction, atomically thin transition metal dichalcogenides are ideal active materials for cavity quantum electrodynamics. Here, the authors embed a WSe2monolayer within a Tamm-plasmon-polariton cavity, and observe exciton-polariton formation at room temperature.