J. C. Ashley

Electron inelastic mean free paths and energy losses in solids II: Electron gas statistical model☆☆☆

Abstract A statistical model for the calculation of inelastic mean free paths and energy losses of electrons in solids is described. Results for the application of the model to the six solid media Al, Au, Ag, Cu, Ni, and Si are presented. Agreement between calculated mean free paths and experimental attenuation lengths indicates that the statistical model provides a useful method in the little-studied electron energy range from a few tens of electron volts to 10 keV.

Electron inelastic mean free paths and energy losses in solids: I. Aluminum metal

Abstract Inelastic mean free paths and energy losses in aluminum metal are calculated for electrons with energies from a few eV to 10 4 eV above the Fermi level. We have represented the contribution from excitations of the valence electrons by using an electron gas model. The effect of damping in the electron gas on the mean free path and energy loss is included within the context of the Mermin-Kliewer-Fuchs model of the electron gas dielectric function. The influence of core polarizability and local field corrections are discussed briefly. The contributions to the mean free path and energy loss of electrons from ionization of inner shells have been evaluated from atomic models. Comparisons are made with experimental data taken over a wide range of energies.

Straggling and plasmon excitation in the energy loss spectra of electrons transmitted through carbon

Abstract A model is described for the calculation of differential inverse mean free paths (DIMFPs) for the inelastic interactions of electrons with solids. The energy loss function Im{-1/ e ( q , ω )} is represented as a sum of Drude-type functions. The adjustable parameters in the energy loss function are fixed by a fit to the energy loss function in the optical limit ( q → 0) obtained from data on the optical constants of glassy carbon. The extension of the optical energy loss function to arbitrary values of q in this model leads to an analytical expression for the DIMFP. Energy loss spectra for low energy electrons (less than 2000 eV) transmitted through carbon foils of various thicknesses are determined by solving the transport equation using a convolution method and the DIMFPs determined as described above. Comparisons of these calculated spectra with those measured by Jacobi show that the model provides a good description of both the broad straggling distribution and the fine structure due to plasmon excitation.

Calculations of mean free paths and stopping powers of low energy electrons (⩽ 10 keV) in solids using a statistical model

A statistical model is described and employed to calculate inverse mean free paths and stopping powers for electrons of energies from a few eV to 10 keV above the Fermi level in Al, Si, Ni, Cu, Ag, and Au. Brief tables of mean free paths and stopping powers for these solids are presented. In some cases graphical displays of inverse mean free paths and stopping powers are also included. The calculations based on this model are discussed and compared with previous work.

Electron Slowing-Down Spectra in Solids'

Some theoretical methods used to describe the interaction of electrons with metals, semiconductors, and insulators are reviewed. Calculations of electron slowing-down spectra using these methods are presented for Al, Cu, Cr, Si, and Al

Inelastic Interactions of Electrons with Polystyrene: Calculations of Mean Free Paths, Stopping Powers, and CSDA Ranges

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Inelastic Interactions of Low-Energy Electrons with Organic Solids: Simple Formulae for Mean Free Paths and Stopping Powers

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Range of Low-Energy Electrons in Solids

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Electron Interaction Cross Sections in Al and Al2O3; Calculations of Mean Free Paths, Stopping Powers, and Electron Slowing-Down Spectra

. Experimental electron slowing-down spectra for these materials are also presented and comparisons with theoretical calculations are discussed. 40 refs. (auth)

Energy Losses and Mean Free Paths of Electrons in Silicon Dioxide

A theoretical description of the inelastic interactions of electrons with solid polystyrene is presented. The response of the valence electrons to energy and momentum transfers is determined by a model insulator theory; carbon K-shell ionization cross sections are derived from atomic, generalized oscillator strengths. Contributions to the inverse mean free path and stopping power due to these two excitation processes are derived and tabulated for incident electrons with energies from 10 eV to 10 keV. Electron ranges in the continuous-slowing-down approximation are calculated and tabulated for electrons with energies from 15 eV to 10 keV.