The study of intensity of surface plasmon in a metal film excited by free electrons

The moving electron as a way of exciting surface plasma polaritons in metal film has attracted much interest in the field of vacuum electronics. In this paper, based on the Drude model, the intensity of excitation surface plasmon polaritons excited by parallel moving electron bunch is studied. Based on Maxwell equations, there are deduced the dispersion relation and basic characteristics of surface plasmon polaritons on the surface of metal film. By the theoretical analysis and CST simulation, SPPs are excited by high-energy electron bunch with a certain electron velocity on the surface of a metal. The width w of the metal film, the ratio of electron velocity to light velocity $\boldsymbol{\beta}$ and the metal film thickness d are mainly discussed on the intensity of surface plasma polaritons.