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 (13)

• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• Exciton Binding Energy and Nonhydrogenic Rydberg Series in Monolayer WS2
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• Valley dynamics probed through charged and neutral exciton emission in monolayer WSe2
• In-plane Propagation of Light in Transition Metal Dichalcogenide Monolayers: Optical Selection Rules
• Identification of excitons, trions and biexcitons in single-layer WS2
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• Valley-Polarized Exciton-Polaritons in a Monolayer Semiconductor
• Spin-flip processes and radiative decay of dark intravalley excitons in transition metal dichalcogenide monolayers
• Dark excitons and the elusive valley polarization in transition metal dichalcogenides
• Anomalous temperature-dependent spin-valley polarization in monolayer WS${}_2$
• Strong coupling between Tamm plasmon polariton and two dimensional semiconductor excitons
• Valley polarized relaxation and upconversion luminescence from Tamm-Plasmon Trion-Polaritons with a MoSe2 monolayer

Cited by in corpus (11)

• Two-dimensional semiconductors in the regime of strong light-matter coupling
• Optical valley Hall effect for highly valley-coherent exciton-polaritons in an atomically thin semiconductor
• 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
• Room Temperature Valley Polarization and Coherence in Transition Metal Dichalcogenide-Graphene van der Waals Heterostructures
• Engineering photonic environments for two-dimensional materials
• Tracking Dark Excitons with Exciton Polaritons in Semiconductor Microcavities
• Valley polarization of exciton-polaritons in monolayer WSe2 in a tunable microcavity
• Magnetic field induced splitting and polarization of monolayer-based valley exciton-polaritons
• 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