Asymmetric production of plasmons by fast charged particles entering or leaving a semi-infinite material through a planar surface at oblique incidence

J. L. GERVASONI; R BARRACHINA; F. NAVARRETE; S. SEGUI; N. R. ARISTA

Aveiro

Conferencia; 11th NANOSMAT 2016; 2016

The study of plasmon excitation is of great relevance for the characterisation of surfaces, thin films, and nanoparticles using different charged-particles spectroscopic techniques.In this work we are interested in analyzing the asymmetry found in the production of plasmons by fast charged particles entering or leaving a semi-infinite material through a planar surface.We employ the specular reflection model and the extended pseudo-medium method [1] in order to assess the energy loss rate due to plasmon excitation along the projectile's trajectory. In particular, we analyze the integration conditions of the transferred momentum, showing that an approximation usually applied in the literature drives to unconsistent results.We obtain results for a variety of experimental settings, spanning a range of velocities and incidence angles to study how the observed asymmetry between incoming and outgoing trajectories depends on these variables.