Exploring the Dielectric Model in the Limit of Low‐Energy Electrons Interacting With Graphene

Abstract

In this work, we present calculations of energy loss spectra corresponding to slow electrons (100 − 1000 eV) interacting with a graphene monolayer. We use a dielectric two-dimensional model for the conductivity developed for more energetic electrons (>50 keV) and explore its applicability in the present range of energies. The studied configuration is comparable with energy loss spectroscopy experiments implemented in a scanning low-energy electron microscope equipped with a time-of-flight device. We analyze both theoretical and experimental spectra in order to understand the structures observed in the latter and to elucidate the processes involved. The calculated spectra reproduce qualitatively the positions of the π and π + σ plasmon peaks.