Skyrmion inertia in synthetic antiferromagnets

Abstract

We describe the dynamics of magnetic skyrmions in synthetic antiferromagnets (SAF), with a finite interlayer coupling. Due to the opposite gyrovector of the skyrmions in the two SAF layers, the coupled skyrmions reach a stationary regime with a spatial separation, in a direction orthogonal to their velocity. As a consequence, and contrary to the ferromagnetic situation, a transient regime necessarily occurs, with a finite acceleration, related to an inertia, and that limits its time response. The formalism developed here, based on two coupled Thiele equations, allows a quantitative description of this phenomenon. The time constant associated to the transient regime scales inversely with the antiferromagnetic coupling constant. We also show that the coupling force reaches a maximal value at a finite skyrmion separation. This sets a maximum velocity limit, beyond which the the coupling force cannot stabilize the bound state.

19 pages, 5 figures

References in corpus (3)

• Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmion at room temperature
• Inertia and chiral edge modes of a skyrmion magnetic bubble
• Fast Vortex Oscillations in a Ferrimagnetic Disk near the Angular Momentum Compensation Point

Cited by in corpus (5)

• Fast current-induced skyrmion motion in synthetic antiferromagnets
• Fundamental Theory of Current-Induced Motion of Magnetic Skyrmions
• Moving skyrmions in Antiferromagnets by Sublattice Displacements
• Antiferromagnetic Skyrmion Scattering Revealed by Direct Time-Resolved Imaging of Collective Dynamics
• Reversal of the skyrmion topological deflection across ferrimagnetic angular momentum compensation