Dynamical synthetic antiferromagnetic skyrmions and skyrmionia
Phys. Rev. Applied 24, 034054 – Published 19 September, 2025
DOI: https://doi.org/10.1103/jssf-k5yr
Abstract
Skyrmions and skyrmionia are topological spin textures with considerable promise for magnetic memory applications and artificial intelligence applications. Except for their static properties, we present the generation and stabilization of dynamic skyrmions and skyrmionia in synthetic antiferromagnet based nanocontact spin-torque nano-oscillators. By increasing the current density, we observe various dynamic states, including the single dynamic droplet, single dynamic skyrmion, double dynamic skyrmions, dynamic SAF skyrmionia, and dynamic SAF skyrmions. These dynamic SAF skyrmions and skyrmionia exhibit pronounced breathing modes and high oscillation frequencies exceeding 10 GHz, even without external magnetic fields. Remarkably, their stability is maintained not by the Dzyaloshinskii-Moriya interaction, but by antiferromagnetic Ruderman-Kittel-Kasuya-Yosida coupling, dipolar interactions, and current-induced Oersted fields. This study demonstrates the existence of dynamic SAF skyrmions and skyrmionia in spin-torque nano-oscillators, paving the way for future innovations in high-frequency skyrmionic devices.
