Photon superbunching in cathodoluminescence of WS2 monolayer

We investigate the luminescence properties and photon statistics of a tungsten disulfide (WS2) monolayer under electron beam excitation [1]. We report the first observation of photon bunching in cathodoluminescence (CL) from a WS2 monolayer, achieving g2(0) = 156 ± 16 at the lowest current attainable by our instrument. To further improve the excitation synchronization and the electron-emitter interaction, we show exemplary that the careful selection of a simple and compact geometry — a thin, monocrystalline gold nanodisk — can be used to realize photon superbunching of g2(0) = 2152 ± 236. This approach to control the electron excitation of excitons in a WS2 monolayer allows for the synchronization of photon emitters in an ensemble, which is important to further advance light information and computing technologies.