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arXiv · 2210.14525

Linearized frequency domain Landau-Lifshitz-Gilbert equation formulation

Zhuonan Lin·Vitaliy Lomakin
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Abstract

We present a general finite element linearized Landau-Lifshitz-Gilbert equation (LLGE) solver for magnetic systems under weak time-harmonic excitation field. The linearized LLGE is obtained by assuming a small deviation around the equilibrium state of the magnetic system. Inserting such expansion into LLGE and keeping only first order terms gives the linearized LLGE, which gives a frequency domain solution for the complex magnetization amplitudes under an external time-harmonic applied field of a given frequency. We solve the linear system with an iterative solver using generalized minimal residual method. We construct a preconditioner matrix to effectively solve the linear system. The validity, effectiveness, speed, and scalability of the linear solver are demonstrated via numerical examples.

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Zhuonan Lin, Vitaliy Lomakin. 2022-10-26. Linearized frequency domain Landau-Lifshitz-Gilbert equation formulation. https://arxiv.org/abs/2210.14525

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