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.
@article{arxiv.2210.14525,
title = {Linearized frequency domain Landau-Lifshitz-Gilbert equation formulation},
author = {Zhuonan Lin and Vitaliy Lomakin},
journal= {arXiv preprint arXiv:2210.14525},
year = {2022}
}