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arXiv · 2110.14333

Constructing coarse-grained skyrmion potentials from experimental data with Iterative Boltzmann Inversion

Abstract

In an effort to understand skyrmion behavior on a coarse-grained level, skyrmions are often described as 2D quasi particles evolving according to the Thiele equation. Interaction potentials are the key missing parameters for predictive modeling of experiments. We apply the Iterative Boltzmann Inversion technique commonly used in soft matter simulations to construct potentials for skyrmion-skyrmion and skyrmion-magnetic material boundary interactions from a single experimental measurement without any prior assumptions of the potential form. We find that the two interactions are purely repulsive and can be described by an exponential function for experimentally relevant skyrmions. This captures the physics on experimental time and length scales that are of interest for most skyrmion applications and typically inaccessible to atomistic or micromagnetic simulations.

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Yuqing Ge, Jan Rothörl, Maarten A. Brems, Nico Kerber, Raphael Gruber, Takaaki Dohi, Mathias Kläui, Peter Virnau. 2021-10-27. Constructing coarse-grained skyrmion potentials from experimental data with Iterative Boltzmann Inversion. https://arxiv.org/abs/2110.14333

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