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arXiv · 1811.04094

Switching of biaxial synthetic antiferromagnets: a micromagentic study

Michael S. Ackermann·Satoru Emori
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Abstract

We simulate the switching behavior of nanoscale synthetic antiferromagnets (SAFs), inspired by recent experimental progress in spin-orbit-torque switching of crystal antiferromagnets. The SAF consists of two ferromagnetic thin films with in-plane biaxial anisotropy and interlayer exchange coupling. Staggered field-like Rashba spin-orbit torques from the opposite surfaces of the SAF induce a canted net magnetization, which triggers an orthogonal torque that drives 90$^\circ$ switching of the Néel vector. Such dynamics driven by the field-like spin-orbit torque allows for faster switching with increased Gilbert damping, without a significant detrimental increase of the threshold switching current density. Our results point to the potential of SAFs as model systems, based on simple ferromagnetic metals, to mimic antiferromagnetic device physics.

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Michael S. Ackermann, Satoru Emori. 2018-11-22. Switching of biaxial synthetic antiferromagnets: a micromagentic study. https://doi.org/10.1063/1.5052156

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