Demonstration of a polariton step potential by local variation of light-matter coupling in a van-der-Waals heterostructure

TL;DR

This paper demonstrates how local modifications of layer number in a van-der-Waals heterostructure can create a polariton step potential at room temperature, enabling precise control of light-matter interactions.

Contribution

It introduces a method to engineer local polaritonic potentials by varying the light-matter coupling strength through layer number adjustments in a heterostructure.

Findings

Local layer variation induces a polaritonic staircase potential.

Room temperature demonstration of local polaritonic control.

Potential for atomically sharp interface engineering.

Abstract

The large oscillator strength of excitons in transition metal dichalcogenide layers facilitates the formation of exciton-polariton resonances for monolayers and van-der-Waals heterostructures embedded in optical microcavities. Here, we show, that locally changing the number of layers in a WSe2/hBN/WSe2 van-der-Waals heterostructure embedded in a monolithic, high-quality-factor cavity gives rise to a local variation of the coupling strength. This effect yields a polaritonic stair case potential, which we demonstrate at room temperature. Our result paves the way towards engineering local polaritonic potentials at length scales down to atomically sharp interfaces, based on purely modifying its real part contribution via the coherent light-matter coupling strength g.