Fig. 4: Optical characterization of a sandwiched OPEN-WSe₂ film.

Integrated intensity from the same area of a Au/monolayer-WSe₂/Au/SiO₂ sample using a scanning confocal PL map (linear color scale) and b remote PL map (logarithmic color scale) with the collection spot fixed at the black dot point and the excitation beam scanned to form the image (scale bar = 10μm). (inset a) histogram of dominant emitter peak energy versus number of emitters in a. c, d second-order photon correlation function g⁽²⁾(t) measurement of the central emitter in b for excitation at the black circle point and remotely at white cross point, respectively. e PL spectra taken at the central emitter while exciting locally (excitation and collection at the black dot) and remotely (excitation at the white cross, collection at the black dot). The scale of the remote spectrum (red curve) is on the right-hand y-axis. f Plot of PL intensity versus distance for every pixel in b. A fit to the most intense (peak intensity) PL data using Equation 1 (red line) has a R² = 0.92, with γ_532nm = 1 μm and γ_WSe2 = 15 μm (Supplementary Fig. 19).