Ab initio calculations of mean free paths and stopping powers
Abstract
A method is presented for first-principles calculations of inelastic mean free paths and stopping powers in condensed matter over a broad energy range. The method is based on {\it ab initio} calculations of the dielectric function in the long wavelength limit using a real-space Green's function formalism, together with extensions to finite momentum transfer. From these results we obtain the loss function and related quantities such as optical-oscillator strengths and mean excitation energies. From a many-pole representation of the dielectric function we then obtain the electron self-energy and inelastic mean free paths (IMFP). Finally using our calculated dielectric function and the optical-data model of Fern\'andez-Varea {\it et al}., we obtain collision stopping powers (CSP) and penetration ranges. The results are consistent with semi-empirical approaches and with experiment.
Keywords
Cite
@article{arxiv.cond-mat/0605135,
title = {Ab initio calculations of mean free paths and stopping powers},
author = {A. P. Sorini and J. J. Kas and J. J. Rehr and M. P. Prange and Z. H. Levine},
journal= {arXiv preprint arXiv:cond-mat/0605135},
year = {2009}
}
Comments
17 p., 8 fig