Fully tunable exciton-polaritons emerging from WS$_{2}$ monolayer excitons in an optical lattice at room temperature

TL;DR

This paper demonstrates room-temperature, fully tunable exciton-polaritons in a WS$_{2}$ monolayer within an optical lattice, enabling reconfigurable photonic emulators with strong light-matter coupling.

Contribution

It introduces a novel platform for reconfigurable polaritonic lattices using WS$_{2}$ monolayers at room temperature, with spectral and coupling tunability.

Findings

Observation of canonical band-structure at room temperature

Frequency reconfigurability exceeding 12 meV

Bandwidth tuning of polaritons by 7 meV

Abstract

Engineering non-linear hybrid light-matter states in tailored optical lattices is a central research strategy for the simulation of complex Hamiltonians. Excitons in atomically thin crystals are an ideal active medium for such purposes, since they couple strongly with light and bear the potential to harness giant non-linearities and interactions while presenting a simple sample-processing and room temperature operability. We demonstrate lattice polaritons, based on an open, high-quality optical cavity, with an imprinted photonic lattice strongly coupled to excitons in a WS$_{2}$ monolayer. We experimentally observe the emergence of the canonical band-structure of particles in a one-dimensional lattice at room temperature, and demonstrate frequency reconfigurability over a spectral window exceeding 12 meV, as well as the systematic variation of the nearest neighbour coupling, reflected by a tuneability in the bandwidth of the p-band polaritons by 7 meV. The technology presented in this work is a critical demonstration towards reconfigurable photonic emulators operated with non-linear photonic fluids, offering a simple experimental implementation and working at ambient conditions.