The role of electronic friction of low-energy recoils in atomic collision cascades

We investigate the influence of low-energy recoils with respect to the electronic excitation of solids generated in atomic collision cascades. It is found that the electronic friction experienced by recoil atoms moving with kinetic energies below 10 eV contributes substantially to the total excitation energy dissipated into electronic degrees of freedom. The collision dynamics, on the other hand, remain virtually unchanged if the friction loss of these particles is switched on or off. This is illustrated by looking at the yield, emission sites and energies of sputtered surface atoms.