Nutational switching in ferromagnets and antiferromagnets

Abstract

It was demonstrated recently that on ultrashort time scales magnetization dynamics does not only exhibit precession but also nutation. Here, we investigate how nutation can contribute to spin switching leading towards ultrafast data writing. We use analytic theory and atomistic spin simulations to discuss the behavior of ferromagnets and antiferromagnets in high-frequency magnetic fields. In ferromagnets, linearly polarized fields align the magnetization perpendicular to the external field, enabling $90^{\circ }$ switching. For circularly polarized fields in the $xy$ plane, the magnetization tilts to the $z$ direction. During this tilting, it rotates around the $z$ axis, allowing $180^{\circ }$ switching. In antiferromagnets, external fields with frequencies higher than the nutation frequency align the order parameter parallel to the field direction, while for lower frequencies it is oriented perpendicular to the field. The switching frequency increases with the magnetic field strength, and it deviates from the Larmor frequency, making it possible to outpace precessional switching in high magnetic fields.

12 pages, 11 figures

References in corpus (1)

• Nutation in antiferromagnetic resonance

Cited by in corpus (5)

• Magneto-optical Kerr effect in ferroelectric antiferromagnetic two-dimensional heterostructures
• Inertial effects in ultrafast spin dynamics
• Magnetic nutation: transient separation of magnetization from its angular momentum
• Micromagnetic study of inertial spin waves in ferromagnetic nanodots
• Theory of tensorial magnetic inertia in terahertz spin dynamics