Surface dielectric functions of a free-electron gas.

J.E. MIRAGLIA; M.S. GRAVIELLE

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

The American Physical Society

Lugar: New York; Año: 2002 vol. 66 p. 32901 - 32907

1050-2947

We investigate the surface dielectric response of a free-electron gas to a projectile moving parallel to the surface. Three theoretical models are examined, viz., the specular reflection and the parallel dispersion models, and a here-proposed axial model. The mean-free path, the stopping, the straggling, and the self-induced potential at the projectile position, are calculated in terms of the distance of the projectile to the surface. Differences at level of energy-loss distribution are found. We conclude that the axial model is reliable, has a simple closed form and permits us to estimate the binary contribution.