Optical emission from rough surfaces irradiated by charged particles

The electron stimulated photon emission from a semi-infinite realistic medium with surface impurities (surface roughness) is considered. A complete solution of the photon yield to second order in the roughness is obtained (SPREE) using the Rayleigh-Fano boundary condition method, which is valid for small roughness. Treating the current quantum mechanically, it is possible to include all quantum corrections and the effect of the crystal potential, which cannot be neglected at grazing incident angles theta el>or approximately=87 degrees . For smaller angles, but cotan theta el<<1, and small correlation lengths (of the order of 250AA) the general result can be carried out analytically. Beyond the well known (cos theta el)-1 photon yield dependence, its velocity dependence is found to be in agreement with experimental results. Finally the results are compared with those of other authors: Ritchie, Sauerbrey et al. (1964).