Observation of macroscopic valley-polarized monolayer exciton-polaritons at room temperature

Abstract

In this letter, we address the chiral properties of valley exciton-polaritons in a monolayer of WS2 in the regime of strong light-matter coupling with a Tamm-Plasmon resonance. We observe that the valley polarization, which manifests in the circular polarization of the emitted photoluminescence, is strongly enhanced in comparison to bare WS2 monolayers, and can even be observed under non-resonant excitation at ambient conditions. We study the relaxation and decay dynamics of exciton-polaritons in our device, and present a microscopic model to explain the wave vector-dependent valley depolarization as an interplay of bright and dark states, electron-hole exchange interaction and the linear polarization splitting inherent to the microcavity.

References in corpus (3)

• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Dark excitons and the elusive valley polarization in transition metal dichalcogenides
• Valley polarized relaxation and upconversion luminescence from Tamm-Plasmon Trion-Polaritons with a MoSe2 monolayer

Cited by in corpus (5)

• Strongly enhanced light-matter coupling of a monolayer WS2 from a bound state in the continuum
• Uncovering Temperature-Dependent Exciton-Polariton Relaxation Mechanisms in Perovskites
• Engineering photonic environments for two-dimensional materials
• Microscopic theory of cavity-confined monolayer semiconductors: polariton-induced valley relaxation and the prospect of enhancing and controlling the valley pseudospin by chiral strong coupling
• Optical Measurement of Pseudo-Spin Texture of the Exciton Fine-Structure in Monolayer WSe2 within the Light Cone