Moving magnets in a micromagnetic finite difference framework

TL;DR

This paper introduces a GPU-accelerated finite difference micromagnetic simulation method that accurately models moving magnets, magnetic friction, and eddy currents, enabling efficient and precise microscale magnetic dynamics analysis.

Contribution

It presents a novel approach combining scalar potential calculation and cubic b-spline interpolation for smooth magnet motion in micromagnetic simulations, including eddy current effects.

Findings

Successful simulation of stick-slip motion in thin films

Demonstration of eddy currents affecting switching times

High computational efficiency achieved with GPU parallelization

Abstract

We present a method and an implementation for smooth linear motion in a finite difference-based micromagnetic simulation code, to be used in simulating magnetic friction and other phenomena involving moving microscale magnets. Our aim is to accurately simulate the magnetization dynamics and relative motion of magnets while retaining high computational speed. To this end, we combine techniques for fast scalar potential calculation and cubic b-spline interpolation, parallelizing them on a Graphics Processing Unit (GPU). The implementation also includes the possibility of explicitly simulating eddy currents in the case of conducting magnets. We test our implementation by providing numerical examples of stick-slip motion of thin films pulled by a spring and the effect of eddy currents on the switching time of magnetic nanocubes.