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arXiv · 1906.05067

Elastic propagation of fast electron vortices through amorphous materials

Stefan Löffler·Stefan Sack·Thomas Schachinger
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Abstract

In this work, we study the elastic scattering behavior of electron vortices when propagating through amorphous samples. We use a formulation of the multislice approach in cylindrical coordinates to theoretically investigate the redistribution of intensity between different angular momentum components due to scattering. To corroborate and elaborate on our theoretical results, we perform extensive numerical simulations on three model systems (Si$_3$N$_4$, Fe$_{0.8}$B$_{0.2}$, Pt) for a wide variety of experimental parameters to quantify the purity of the vortices, the net angular momentum transfer, and the variability of the results with respect to the random relative position between the electron beam and the scattering atoms. These results will help scientists to further improve the creation of electron vortices and enhance applications involving them.

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Stefan Löffler, Stefan Sack, Thomas Schachinger. 2019-06-12. Elastic propagation of fast electron vortices through amorphous materials. https://doi.org/10.1107/s2053273319012889

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