Enhanced Polariton Interactions in Suspended WS₂ Monolayer Microcavity.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Optoelectronics

Background:

• Transition-metal dichalcogenides (TMDs) monolayers exhibit strong exciton resonances crucial for light-matter interactions.
• Substrate interactions in TMDs cause excitonic losses, limiting their use in optical nonlinearities and exciton-polariton platforms.
• Suspended TMD monolayers can eliminate substrate-induced losses, enabling exploration of intrinsic material properties.

Purpose of the Study:

• To develop a novel fabrication method for suspended TMD monolayers within planar microcavities.
• To investigate the enhancement of strong coupling and polaritonic interactions in suspended WS2 monolayers.
• To overcome substrate limitations and achieve intrinsic performance in 2D material-based polaritonic systems.

Main Methods:

• Fabrication of a planar microcavity containing a suspended tungsten disulfide (WS2) monolayer.
• Experimental characterization of light-matter interactions and strong coupling at room temperature.
• Comparison of performance with dielectric-filled microcavity systems.

Main Results:

• Demonstration of a 2-fold enhancement in strong coupling at room temperature.
• Observation of increased exciton binding energy and reduced overall losses in suspended WS2.
• Significant amplification of spin-dependent polaritonic interactions, achieving a record exciton interaction constant.

Conclusions:

• Suspended WS2 monolayers in microcavities significantly enhance strong coupling and polaritonic interactions.
• This approach minimizes losses, allowing 2D materials to approach their intrinsic performance limits.
• The novel fabrication method paves the way for high-performance 2D material-based polaritonic devices.