Two-dimensional metal-chalcogenide films in tunable optical microcavities

TL;DR

This paper demonstrates tunable optical microcavities with embedded 2D metal-chalcogenide films, significantly enhancing photoluminescence properties and enabling potential applications in light-emitting devices and cavity QED with layered materials.

Contribution

It introduces tunable microcavities with embedded monolayer MoS2 or GaSe films, showing enhanced emission and spectral control, advancing 2D material photonics.

Findings

PL emitted in narrow, tunable cavity modes with Q up to 7400

Achieved 10-fold shortening of PL lifetime via Purcell effect

Potential for microcavity-enhanced 2D material devices

Abstract

Quasi-two-dimensional (2D) films of layered metal-chalcogenides have attractive optoelectronic properties. However, photonic applications of thin films may be limited owing to weak light absorption and surface effects leading to reduced quantum yield. Integration of 2D films in optical microcavities will permit these limitations to be overcome owing to modified light coupling with the films. Here we present tunable microcavities with embedded monolayer MoS2 or few monolayer GaSe films. We observe significant modification of spectral and temporal properties of photoluminescence (PL): PL is emitted in spectrally narrow and wavelength-tunable cavity modes with quality factors up to 7400; PL life-time shortening by a factor of 10 is achieved, a consequence of Purcell enhancement of the spontaneous emission rate. This work has potential to pave the way to microcavity-enhanced light-emitting devices based on layered 2D materials and their heterostructures, and also opens possibilities for cavity QED in a new material system of van der Waals crystals.