Path-length-dependent aloof excitation of surface modes

Abstract

A simple model is proposed which approximately accounts for the finite duration of the aloof interaction of fast electron beams with bounded media of finite extent in the beam direction. Beam trajectories parallel to the solid surface arc investigated. Quantum corrections to the classical predictions of the probability of excitation of surface modes arc shown to be most pronounced for low beam energies and to increase for increasing distance from the beam to the surface.