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arXiv · 2306.00271

A fast and accurate computation method for reflective diffraction simulations

Shuhei Kudo·Yusaku Yamamoto·Takeo Hoshi
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Abstract

We present a new computation method for simulating reflection high-energy electron diffraction and the total-reflection high-energy positron diffraction experiments. The two experiments are used commonly for the structural analysis of material surface. The present paper improves the conventional numerical method, the multi-slice method, for faster computation, since the present method avoids the matrix-eigenvalue solver for the computation of matrix exponentials and can adopt higher-order ordinary differential equation solvers. Moreover, we propose a high-performance implementation based on multi-thread parallelization and cache-reusable subroutines. In our tests, this new method performs up to 2,000 times faster than the conventional method.

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Shuhei Kudo, Yusaku Yamamoto, Takeo Hoshi. 2023-06-01. A fast and accurate computation method for reflective diffraction simulations. https://arxiv.org/abs/2306.00271

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