In this talk, I will present a new method for the simulation of scanning transmission electron microscopy (STEM) images. The simulation of STEM images is a computationally challenging task because the classical approach using the Multislice algorithm requires solving the Schrödinger PDE many times for a single pixel in the output image, resulting in very long computation times. In order to reduce the computation time, a new algorithm termed PRISM has recently been developed. This algorithm makes use of the linearity of the Schrödinger equation and propagates a small set of certain elementary wave functions through the specimen, from which the original probe wave functions can be reconstructed with linear combinations. Although this is a mathematically elegant way to reduce the computation time, it introduces several practical problems. I will present a new point of view on this problem by approximating the probe wave functions by different sets of functions that are well localized in real space coordinates, which avoids the computational problems with PRISM while keeping the same computational speedup.
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