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arXiv · 1903.05415

Higher-order linearly implicit full discretization of the Landau--Lifshitz--Gilbert equation

Georgios Akrivis·Michael Feischl·Balázs Kovács·Christian Lubich
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Abstract

For the Landau--Lifshitz--Gilbert (LLG) equation of micromagnetics we study linearly implicit backward difference formula (BDF) time discretizations up to order $5$ combined with higher-order non-conforming finite element space discretizations, which are based on the weak formulation due to Alouges but use approximate tangent spaces that are defined by $L^2$-averaged instead of nodal orthogonality constraints. We prove stability and optimal-order error bounds in the situation of a sufficiently regular solution. For the BDF methods of orders $3$ to~$5$, this requires %a mild time step restriction $\tau \leqslant ch$ and that the damping parameter in the LLG equations be above a positive threshold; this condition is not needed for the A-stable methods of orders $1$ and $2$, for which furthermore a discrete energy inequality irrespective of solution regularity is proved.

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Georgios Akrivis, Michael Feischl, Balázs Kovács, Christian Lubich. 2019-03-13. Higher-order linearly implicit full discretization of the Landau--Lifshitz--Gilbert equation. https://arxiv.org/abs/1903.05415

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