Structure-Dependent Dynamics of Quantum Emitters in Single-Layer WSe₂.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Optics

Background:

• Single-layer tungsten diselenide (WSe2) exhibits localized states suitable for solid-state quantum light sources.
• Formation of these quantum emitters relies on localized tensile strain but is generally robust to various environmental factors.
• Intrasample heterogeneity complicates the study of individual quantum emitters and hinders cross-sample comparisons.

Purpose of the Study:

• To statistically investigate the impact of sample architecture on the photoluminescence dynamics of WSe2 quantum emitters.
• To understand how material quality, substrate composition, and nanoscale stressors influence emitter behavior at an ensemble level.
• To identify structure-property relationships crucial for advancing WSe2-based quantum light sources.

Main Methods:

• Statistical comparison of emitter populations across samples with varied material quality, substrate, and nanoscale stressors.
• Formulation of numerical descriptors for emitter photoluminescence transients.
• Analysis of emitter dynamics under different sample architectures.

Main Results:

• Emitter dynamics are affected at the ensemble level by sample architecture.
• Substrate composition shows no significant impact on emitter dynamics.
• High-quality WSe2 on gold nanocones exhibits reduced nonlinear relaxation and exciton diffusion to emitter sites.

Conclusions:

• Statistical comparison is an effective method for revealing structure-property relationships in quantum emitters.
• Optimizing sample architecture, specifically material quality and nanoscale features, is key to controlling WSe2 quantum emitter dynamics.
• This research provides insights for the development of WSe2 into efficient quantum light sources.