Tamm-plasmon exciton-polaritons in monolayer WS₂ at room temperature

Exciton polaritons are bosonic quasi-particles that arise from the quantum superposition of photons and excitons. It can be utilized in the design of polaritonic devices such as low-threshold lasers and optical switches. However, exciton-polaritons are typically observed at low temperatures due to the small binding energy of excitons in traditional inorganic semiconductors. Here, using Tamm microcavities, demonstrate a sandwich-structured WS 2 -based device that realizes exciton polaritons at room-temperature. A clear anti-crossing is observed in both angular-resolved reflectivity and photoluminescence (PL) spectra with a pronounced Rabi splitting of 39.2 meV. The realization of room temperature exciton polaritons is conducive to the practical device applications of exciton-polaritons.