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arXiv · 0807.2387

Fast computation of magnetostatic fields by Non-uniform Fast Fourier Transforms

Evaggelos Kritsikis·Jean-Christophe Toussaint·Olivier Fruchart
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Abstract

The bottleneck of micromagnetic simulations is the computation of the long-ranged magnetostatic fields. This can be tackled on regular N-node grids with Fast Fourier Transforms in time N logN, whereas the geometrically more versatile finite element methods (FEM) are bounded to N^4/3 in the best case. We report the implementation of a Non-uniform Fast Fourier Transform algorithm which brings a N logN convergence to FEM, with no loss of accuracy in the results.

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Evaggelos Kritsikis, Jean-Christophe Toussaint, Olivier Fruchart. 2008-07-15. Fast computation of magnetostatic fields by Non-uniform Fast Fourier Transforms. https://doi.org/10.1063/1.2995850

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