Theoretical Bounds on Electron Energy Filtering in Disordered Nanomaterials

This manuscript presents a theoretical model for determining the electron energy filtering properties of nanocomposite materials. Individual nanoparticles can serve as energy filters for tunneling electrons due their discretized energy levels. Nanomaterials comprised of many individual nanoparticles can in principle serve the same purpose, however, particle polydispersity can lead to an additional source of energetic broadening. We describe a simple theoretical model that includes the effects of discrete energy levels and inhomogeneous broadening. We use this model to identify the material parameters needed for effective energy filtering by quantum dot solids.

Theoretical Bounds on Electron Energy Filtering in Disordered Nanomaterials

This manuscript presents a theoretical model for determining the electron energy filtering properties of nanocomposite materials. Individual nanoparticles can serve as energy filters for tunneling electrons due their discretized energy levels. Nanomaterials comprised of many individual nanoparticles can in principle serve the same purpose, however, particle polydispersity can lead to an additional source of energetic broadening. We describe a simple theoretical model that includes the effects of discrete energy levels and inhomogeneous broadening. We use this model to identify the material parameters needed for effective energy filtering by quantum dot solids.

Evaluation of phonon scattering in electron diffraction using image plates and electron energy filtering

There have been few studies of thermal diffuse scattering (TDS) by electron diffraction although this scattering is easily observed. The TDS intensity distribution is as a rule strongly anisotropic which can be ascribed to scattering from individual phonon modes. Results reported so far in the literature are all based on qualitative or semi-quantitative use of the observed intensity distributions. However, at present several new methods (energy filters, imaging plate, CCD, digitized film) are available to extract data for detailed quantitative interpretation. In the present work the Zeiss 912 Omega energy filtering microscope has been used, combined with the Fuji Imaging Plate and a low temperature specimen holder. This opens new possibilities both for the study of soft modes and other TDS phenomena related to phase transitions, and also static disorder and order-disorder effects. By comparison with synchrotron work on TDS , crystals may be very much smaller and count rates are much higher. However, multiple scattering and Kikuchi lines may complicate the interpretation unless thin samples are used.

Scanning Electron Diffraction Attachment with Energy Filter

The advantages of scanning electron diffraction with electron energy filtering over conventional electron diffraction have been fairly widely described, and, more recently, the use of such systems in conjunction with transmission electron microscopes has been reported. By means of scanning diffraction, the electron intensities in a diffraction pattern may be measured and plotted directly on an XY recorder without the inaccuracy and inconvenience of the normal photographic-densitometric process; and the use of an energy filter to remove electrons that have suffered an energy loss allows direct measurement of the diffracted intensities of the elastically-scattered electrons. In this paper, we describe a Scanning Electron Diffraction Attachment (SEDA) with electrostatic energy filter that has been constructed for use with the AEI EM6 and EM8 series of electron microscopes.