ION-INDUCED ELECTRON-EMISSION IN GRAZING ION SURFACE COLLISIONS

The distribution of low-energy electrons emitted from a solid when a swift ion interacts with its surface under grazing incidence conditions is obtained using first-order time-dependent perturbation theory. The response of the surface is calculated from the specular-reflection model and the random-phase approximation for the dielectric function of the bulk material. The electrons are described in terms of independent states, that are solutions of the Schrodinger equation with a finite square barrier potential. A broad peak in energy, corresponding to the excitation of surface plasmons, is predicted to appear in the energy spectrum. The angular dependence of the emission is also analyzed. The electrons are found to be preferentially emitted in the normal and forward directions.