Contribution of multiple plasmon scattering in low-angle electron diffraction investigated by energy-filtered atomically resolved 4D-STEM

We report the influence of multiple plasmon losses on the dynamical diffraction of high-energy electrons, in a scanning transmission electron microscopy (STEM) study. Using an experimental setup enabling energy-filtered momentum-resolved STEM, it is shown that the successive excitation of up to five plasmons within the imaged material results in a subsequent and significant redistribution of low-angle intensity in diffraction space. An empirical approach, based on the convolution with a Lorentzian kernel, is shown to reliably model this redistribution in dependence of the energy-loss. Our study demonstrates that both the significant impact of inelastic scattering in low-angle diffraction at elevated specimen thickness and a rather straightforward model can be applied to mimic multiple plasmon scattering, which otherwise is currently not within reach for multislice simulations due to computational complexity. (C) 2022 Author(s).All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY)license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

This study reports the impact of multiple plasmon losses on the dynamical diffraction of high-energy electrons in a scanning transmission electron microscopy (STEM) study. By using an experimental setup enabling energy-filtered momentum-resolved STEM, it is demonstrated that the successive excitation of multiple plasmons within the imaged material leads to a significant redistribution of low-angle intensity in diffraction space. The study shows that a simple model based on convolution with a Lorentzian kernel can effectively simulate this redistribution in dependence of the energy loss.