Spontaneous Emission Enhancement in Strain-Induced WSe₂ Monolayer-Based Quantum Light Sources on Metallic Surfaces

Atomic monolayers of transition metal dichalcogenides represent an emerging material platform for the implementation of ultracompact quantum light emitters via strain engineering. In this framework, we discuss experimental results on creation of strain induced single photon sources using a WSe2 monolayer on a silver substrate, coated with a very thin dielectric layer. We identify quantum emitters that are formed at various locations in the sample. Their emission is highly linearly polarized, stable in linewidth, and decay times down to 100 ps are observed. We provide numerical calculations of our monolayer-metal device platform to assess the strength of the radiative decay rate enhancement by the presence of the plasmonic structure. We believe that our results represent a crucial step toward the ultracompact integration of high performance single photon sources in nanoplasmonic devices and circuits.