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arXiv · 1701.05810

Conjugate gradient methods in micromagnetics

J. Fischbacher·A. Kovacs·H. Oezelt·T. Schrefl·L. Exl·J. Fidler·D. Suess·N. Sakuma·M. Yano·A. Kato·T. Shoji·A. Manabe
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Abstract

Conjugate gradient methods for energy minimization in micromagnetics are compared. When the step length in the line search is controlled, conjugate gradient techniques are a fast and reliable way to compute the hysteresis properties of permanent magnets. The method is applied to investigate demagnetizing effects in NdFe12 based permanent magnets. The reduction of the coercive field by demagnetizing effects is 1.4 T at 450 K.

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J. Fischbacher, A. Kovacs, H. Oezelt, T. Schrefl, L. Exl, J. Fidler, D. Suess, N. Sakuma, M. Yano, A. Kato, T. Shoji, A. Manabe. 2017-01-20. Conjugate gradient methods in micromagnetics. https://doi.org/10.1063/1.4981902

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