Substrate-induced effects on the dynamics of quantum light emitters in 2D semiconductors

2D semiconductors host quantum emitters that exhibit single-photon emission. These emitters have the potential to be used as light sources in next-generation quantum devices due to their sensitivity to external stimuli and optical addressability. Here we present an all-optical study on the effects that the supporting substrate has on the optical properties of quantum emitters hosted in single-layer WSe2 (1L-WSe2) on SiO2, hBN, and patterned gold nano-cone substrates. In this study, we leverage statistical analysis methods to deduce the effects that the substrate has on the color, lifetime, and brightness of the quantum emitters. The statistical analysis of the excited state dynamics of the emitters is achieved with a straightforward numerical method that quantifies the homogeneity of the photoluminescence time-transient. The numerical method effectively describes the complex dynamics of excitation and relaxation of the emitters and facilitates statistical comparison between the distinct emitter-substrate permutations. Systematic differences in the formation physics of the states after optical excitation between the distinct systems are observed. We find that 1L-WSe2 on gold nano-cones produces the most homogenous distribution of quantum emitter states. These results lend valuable insight into how substrate choice and precise nanofabrication of the surrounding environment and strain stimuli can optimize quantum emitters hosted in 2D semiconductors.