Optical Valley Hall Effect based on Transitional Metal Dichalcogenide cavity polaritons

TL;DR

This paper investigates the dispersion of spinor exciton-polaritons in a TMD monolayer microcavity, demonstrating how reduced disorder scattering enables observation of the optical Valley Hall effect through valley-polarized domain formation.

Contribution

It introduces a theoretical framework for exciton-polaritons in TMD monolayers considering spin-orbit coupling and disorder, revealing conditions for the optical Valley Hall effect.

Findings

Disorder reduction enhances polariton coherence.

Optical Valley Hall effect leads to valley-polarized domains.

Spinor polariton dispersion is influenced by excitonic and photonic spin-orbit coupling.

Abstract

We calculate the dispersion of spinor exciton-polaritons in a planar microcavity with its active region containing a single Transitional Metal Dichalcogenide (TMD) monolayer, taking into account excitonic and photonic spin-orbit coupling. We consider the radial propagation of polaritons in presence of disorder. We show that the reduction of the disorder scattering induced by the formation of polariton states allows to observe an optical Valley Hall effect, namely the coherent precession of the locked valley and polarization pseudospins leading to the formation of spatial valley-polarized domains.