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arXiv · 2002.11401

flatspin: A Large-Scale Artificial Spin Ice Simulator

Johannes H. Jensen·Anders Strømberg·Odd Rune Lykkebø·Arthur Penty·Magnus Själander·Erik Folven·Gunnar Tufte
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Abstract

We present flatspin, a novel simulator for systems of interacting mesoscopic spins on a lattice, also known as artificial spin ice (ASI). Our magnetic switching criteria enables ASI dynamics to be captured in a dipole model. Through GPU acceleration, flatspin can simulate realistic dynamics of millions of magnets within practical time frames. We demonstrate flatspin's versatility through the reproduction of a diverse set of established experimental results from the literature. In particular, magnetization details of "pinwheel" ASI during field-driven reversal have been reproduced, for the first time, by a dipole model. The simulation framework enables quick exploration and investigation of new ASI geometries and properties at unprecedented speeds.

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Johannes H. Jensen, Anders Strømberg, Odd Rune Lykkebø, Arthur Penty, Magnus Själander, Erik Folven, Gunnar Tufte. 2020-02-26. flatspin: A Large-Scale Artificial Spin Ice Simulator. https://doi.org/10.1103/physrevb.106.064408

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