Nonrelativistic electron–electron Møller scattering in a nonadiabatic tunnel-ionizing surface plasmon field

Abstract

AbstractUltrafast processes occurring on nanoscale surfaces can be probed with ultrafast low-energy electron pulses. Specifically, for metallic samples, the interaction of free electrons with surface plasmon fields provides insight into the nanoscale electron dynamics at the surface. Current models and experiments include the interaction of electrons with the sample, but ignore electron–electron and electron–plasmon interactions. Here we show that secondary electrons and their interaction with the incident primary electrons via nonrelativistic Møller scattering in the presence of optical and surface plasmon fields significantly alters the electron dynamics probed with ultrafast low-energy electron microscopy. Modeling this electron–plasmon interaction is key for interpreting ultrafast electron dynamics on metallic surfaces.