Dataset supporting the publication: "Sub-diffraction-resolved spatial distribution of emitting excitons in STM-induced luminescence of 2D semiconductors via Richardson-Lucy deconvolution"

Two-dimensional (2D) semiconductors such as transition metal dichalcogenide monolayers are the building blocks of a future generation of optoelectronic devices, and in particular, of ultrathin electroluminescent devices. The diffusion of charge carriers and excitons (bound electron-hole pairs) and their interactions with defects play a key role in the electroluminescence properties of these materials. Understanding and controlling these processes is crucial for the performance of future devices based on these materials. Unfortunately, exciton diffusion occurs at scales (20 - 200 nm) that are smaller than the spatial resolution of far-field optical microscopes (200 - 500 nm), which are limited by the diffraction of light. There are nanoscopy techniques coupling light and scanning near-field probes that overcome this diffraction limit. Recently, the electroluminescence properties of 2D semiconductors have been mapped at the nanoscale by recording light induced by tunneling current under the tip of a scanning tunneling microscope (STM) scanned over the sample. However, such techniques provide no information on the diffusion of charge carriers and excitons, as they are not sensitive to the spatial distribution of emission around the excitation source. At each tip position, the signal emitted by the entire sample, regardless of its source, is integrated. In this work, we demonstrate a solution to this problem: we combine tunneling-current excitation under the tip of an STM (for extremely local excitation), wide-field optical microscopy (to image the spatial distribution of the emission), and deconvolution of optical microscopy images using an iterative Richardson-Lucy algorithm (to achieve spatial resolution beyond the diffraction limit). In this way, we reconstruct spatial emission distributions around the excitation point that have full widths at half maximum as small as λ0/(9.4 ± 0.7) (λ0 is the emission wavelength), where the resolution of the optical microscope is at best λ0/2.98 (Abbe criterion) or λ0/2.44 (Rayleigh criterion). This result corresponds to an improvement in spatial resolution of at least a factor of 3. One reason why this has never been done before is that this type of deconvolution requires knowledge of the point spread function (PSF), which is generally very difficult to define for this type of combination of optical microscopy and scanning probes. Here, we overcome this difficulty by using known exciton properties to simulate the PSF as the image of an emitting exciton. This dataset includes all raw data corresponding to the findings in the publication "Sub-diffraction-resolved spatial distribution of emitting excitons in STM-induced luminescence of 2D semiconductors via Richardson-Lucy deconvolution" by Elysé Laurent, Ricardo Javier Peña Román, Sarah Miller, Aditi Raman Moghe, Etienne Lorchat, Séverine Le Moal, Elizabeth Boer-Duchemin, Luiz Fernando Zagonel, Stéphane Berciaud, and Eric Le Moal.