Microcavity enhanced single photon emission from two-dimensional WSe2

TL;DR

This study demonstrates coupling of WSe2 bound excitons to microcavities, significantly enhancing photon emission and efficiency, advancing the development of monolayer-based single photon sources for quantum technologies.

Contribution

It introduces a method to couple WSe2 excitons to microcavities, achieving increased photon flux and Purcell enhancement, which was not previously demonstrated.

Findings

Photon flux increased five-fold.

Purcell factor up to 8 achieved.

Quantum efficiency of 0.46 measured.

Abstract

Atomically flat semiconducting materials such as monolayer WSe$_2$ hold great promise for novel optoelectronic devices. Recently, quantum light emission has been observed from bound excitons in exfoliated WSe$_2$. As part of developing optoelectronic devices, the control of the radiative properties of such emitters is an important step. Here we report the coupling of a bound exciton in WSe$_2$ to open microcavities. We use a range of radii of curvature in the plano-concave cavity geometry with mode volumes in the $\lambda^3$ regime, giving Purcell factors of up to 8 while increasing the photon flux five-fold. Additionally we determine the quantum efficiency of the single photon emitter to be $\eta = 0.46 \pm 0.03$. Our findings pave the way to cavity-enhanced monolayer based single photon sources for a wide range of applications in nanophotonics and quantum information technologies.