Superbunching in cathodoluminescence: a master equation approach

Photon superbunching in cathodoluminescence of excitons in WS2monolayer

“…The fit results clearly demonstrate the brightening of CL intensity after adding a gold nanodisk, which is due to the increase in probability of electrons to interact with the sample. Such a change in excitation efficiency improves the synchronization of an ensemble, which results in increase of the degree of photon bunching according to equation (1) [5,8], which we observe in figure 4(c).…”

“…Moderate photon bunching-with a g 2 (0) < 2 second-order auto-correlation functionis characteristic for thermal light, for example the solar radiation of the Sun was measured to be g 2 (0) ≃ 1.6 [6]. The generation of superthermal light with g 2 (0) > 2 has been observed under the electron-beam excitation, namely in cathodoluminescence (CL) [5,7], which was theoretically described by the quantum master equation method [8]. The temporal correlation of CL photons with a Hanbury Brown and Twiss (HBT) interferometer gives an insight into coherent and incoherent processes in electron-matter interaction [9].…”

“…A decrease of the electron-beam current to sub-pA is expected to further increase the g 2 (0)-values, however such low currents are unattainable by common commercial scanning electron microscopes. Therefore, to further boost the photon bunching, ensembles consisting of identical and densely localized emitters within a sub-wavelength volume are needed [4,8], while a geometry increasing the probability of electronemitter interaction would increase the brightness of the source.…”