Controlling excitons in an atomically thin membrane with a mirror

TL;DR

This paper presents a method to dynamically control excitons in a monolayer MoSe2 by suspending it over a mirror and adjusting the distance to modulate optical properties, enabling advances in quantum optics.

Contribution

The study introduces electromechanical control of exciton-photon interactions in atomically thin semiconductors using a suspended heterostructure over a mirror, a novel approach.

Findings

Reversible modulation of exciton absorption and emission.

Control over exciton-photon coupling via distance adjustment.

Potential applications in quantum optomechanics and photonics.

Abstract

We demonstrate a new approach for dynamically manipulating the optical response of an atomically thin semiconductor, a monolayer of MoSe2, by suspending it over a metallic mirror. First, we show that suspended van der Waals heterostructures incorporating a MoSe2 monolayer host spatially homogeneous, lifetime-broadened excitons. Then, we interface this nearly ideal excitonic system with a metallic mirror and demonstrate control over the exciton-photon coupling. Specifically, by electromechanically changing the distance between the heterostructure and the mirror, thereby changing the local photonic density of states in a controllable and reversible fashion, we show that both the absorption and emission properties of the excitons can be dynamically modulated. This electromechanical control over exciton dynamics in a mechanically flexible, atomically thin semiconductor opens up new avenues in cavity quantum optomechanics, nonlinear quantum optics, and topological photonics.