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Surface Corrections To Bulk Energy Losses In Scanning Transmission Electron Microscopy Of Spheres, A. Rivacoba, P. M. Echenique
Surface Corrections To Bulk Energy Losses In Scanning Transmission Electron Microscopy Of Spheres, A. Rivacoba, P. M. Echenique
Scanning Microscopy
The interaction of a fast electron penetrating a spherical target is studied, in the frame of the classical dielectric theory. Expressions for ω the Fourier component of the induced scalar field and energy loss probability are obtained. The reduction in the bulk loss probability due to the surface boundary correction is calculated to all orders in a multipole expansion. The dependence of this correction on the impact parameter and on the radius of the sphere is also studied and compared with the results for films.
Plasmons In Scanning Transmission Electron Microscopy Electron Spectra, R. H. Ritchie, A. Howie, P. M. Echenique, G. J. Basbas, T. L. Ferrell, J. C. Ashley
Plasmons In Scanning Transmission Electron Microscopy Electron Spectra, R. H. Ritchie, A. Howie, P. M. Echenique, G. J. Basbas, T. L. Ferrell, J. C. Ashley
Scanning Microscopy
A general self-energy formulation of the interaction between an electron in a scanning transmission electron microscope (STEM) and a localized target is given. We prove a theorem relating the probability of energy transfer to that calculated classically. Local dielectric theory of target excitation for various geometries is discussed. The problem of localization of initially unlocalized excitations in the valence band of solids is treated by transforming cross sections differential in momentum transfer into dependence on an impact parameter variable. We are thereby able to account for experimental data in scanning electron microscopy (SEM) that show high spatial resolution.
Interband Transitions In Electron Energy Loss Spectrometry, P. Schattschneider, P. Pongratz
Interband Transitions In Electron Energy Loss Spectrometry, P. Schattschneider, P. Pongratz
Scanning Microscopy
Electron energy loss spectrometry (EELS) allows one to experimentally obtain the dielectric permittivity 𝜀:(ω, q) as a function of frequency ω and wave vector if. From 𝜀 information on inter band transitions in the probed medium can be drawn. In EELS, inter band transitions are screened by the movement of the loosely bound valence or conduction electrons. The screening effect may enhance or attenuate the strength of transitions, and tends to shift the frequencies of resonant oscillations. Another aspect of screening is the occurrence of longitudinal modes in the spectrum. So, great care has to be taken in interpreting …
Monte Carlo Calculations Of Secondary Electron Emission, Suichu Luo, David C. Joy
Monte Carlo Calculations Of Secondary Electron Emission, Suichu Luo, David C. Joy
Scanning Microscopy
Monte Carlo calculations of secondary electron (SE) generation have been performed using a hybrid model of the exponential decay law and cascade multiplication process. The contributions of both valence and core electron excitations, and the production of secondaries by the volume plasmon decay, have been included. The calculation has been extended to include SE's with energies up to half the incident beam energy. The SE yield δSE1 component due to excitation by primary electrons, the SE yield δSE2 due to excitation by backscattered electrons, and the β coefficient are estimated using this model. Calculated SE yields, energy distributions, …