Picture child's feet next to pens, pencils and paper

Open Access research that is helping to improve educational outcomes for children

Strathprints makes available scholarly Open Access content by researchers in the School of Education, including those researching educational and social practices in curricular subjects. Research in this area seeks to understand the complex influences that increase curricula capacity and engagement by studying how curriculum practices relate to cultural, intellectual and social practices in and out of schools and nurseries.

Research at the School of Education also spans a number of other areas, including inclusive pedagogy, philosophy of education, health and wellbeing within health-related aspects of education (e.g. physical education and sport pedagogy, autism and technology, counselling education, and pedagogies for mental and emotional health), languages education, and other areas.

Explore Open Access education research. Or explore all of Strathclyde's Open Access research...

Diffraction effects and inelastic electron transport in angle-resolved microscopic imaging applications

Winkelmann, A. and Nolze, G. and Vespucci, S. and Gunasekar, N. and Trager-Cowan, C. and Vilalta-Clemente, A. and Wilkinson, A. J. and Vos, M. (2017) Diffraction effects and inelastic electron transport in angle-resolved microscopic imaging applications. Journal of Microscopy. ISSN 0022-2720

[img]
Preview
Text (Winkelmann-etal-2017-JM-Diffraction-effects-and-inelastic-electron-transport-in-angle)
Winkelmann_etal_2017_JM_Diffraction_effects_and_inelastic_electron_transport_in_angle.pdf
Final Published Version
License: Creative Commons Attribution 4.0 logo

Download (6MB) | Preview

Abstract

We analyze the signal formation process for scanning electron microscopic imaging applications on crystalline specimens. In accordance with previous investigations, we find nontrivial effects of incident beam diffraction on the backscattered electron distribution in energy and momentum. Specifically, incident beam diffraction causes angular changes of the backscattered electron distribution which we identify as the dominant mechanism underlying pseudocolor orientation imaging using multiple, angle-resolving detectors. Consequently, diffraction effects of the incident beam and their impact on the subsequent coherent and incoherent electron transport need to be taken into account for an in-depth theoretical modeling of the energy and momentum distribution of electrons backscattered from crystalline sample regions. Our findings have implications for the level of theoretical detail that can be necessary for the interpretation of complex imaging modalities such as electron channeling contrast imaging (ECCI) of defects in crystals. If the solid angle of detection is limited to specific regions of the backscattered electron momentum distribution, the image contrast that is observed in ECCI and similar applications can be strongly affected by incident beam diffraction and topographic effects from the sample surface. As an application, we demonstrate characteristic changes in the resulting images if different properties of the backscattered electron distribution are used for the analysis of a GaN thin film sample containing dislocations.