In this work we present a new approach for simulation of energy-filtered HRTEM images by back-propagating the electron beam. Here, the back-propagation means that we consider the fast electrons going in the opposite way through the microscope: from a detector through a specimen, where they undergo an energy-gain process, and then they continue to the source. We show that this time-reversed approach is computationally feasible and can bring consistent results. In this new approach, real collection angle becomes a convergence angle of the simulated probe and the real convergence angle becomes the simulated collection angle, as shown in the scheme below. In this new simulation setup we use small collection angles in order to mimic nearly parallel illumination in HRTEM. The “probe”, on the contrary, has a large convergence angle, because for HRTEM image simulation wide objective apertures are used. The contrast transfer function of the imaging system is inverted by changing the sign of aberrations. This reciprocal approach is well suited to generalize the in-house code developed for energy-filtered STEM simulations using combined Multislice/Bloch-waves approach . We can now switch between different simulation modes, e.g., energy-filtered TEM and STEM, by employing different sets of parameters in the code. It allows to avoid multiple multislice evaluations at each atom position, instead it requires separate calculation for each pixel of the desired EF-HRTEM image, which is often a smaller computational cost. The mathematical proof of the concept will be outlined. Simulated energy-filtered HRTEM images of selected materials, such as STO or LSMO based on this approach will be presented as well.
 J. Rusz, S. Bhowmick, M. Eriksson, N. Karlsson, Phys. Rev. B 89, 134428 (2014).
To cite this abstract:Dmitry Tyutyunnikov, Axel Lubk, Jan Rusz; Simulation of elastic and inelastic electron scattering in EF-HRTEM mode by back-propagation of electron beam.. The 16th European Microscopy Congress, Lyon, France. https://emc-proceedings.com/abstract/simulation-of-elastic-and-inelastic-electron-scattering-in-ef-hrtem-mode-by-back-propagation-of-electron-beam/. Accessed: December 1, 2022
EMC Abstracts - https://emc-proceedings.com/abstract/simulation-of-elastic-and-inelastic-electron-scattering-in-ef-hrtem-mode-by-back-propagation-of-electron-beam/