Switching of biaxial synthetic antiferromagnets: a micromagentic study

We simulate the switching behavior of nanoscale synthetic antiferromagnets, inspired by recent experimental progress in spin-orbit-torque switching of crystal antiferromagnets. The synthetic antiferromagnet consists of two ferromagnetic thin films with in-plane biaxial anisotropy and interlayer exchange coupling, which leads to enhanced stability against external field perturbations compared to single-layer ferromagnets. Switching between the orthogonal easy axes is enabled by current-induced Rashba spin-orbit fields from the opposite surfaces of the synthetic antiferromagnet. The use of 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 these model systems, based on simple ferromagnetic metals, to mimic antiferromagnetic device physics.