Thermal Evolution of Skyrmion Formation Mechanism in Chiral Multilayer Films

Magnetic skyrmions form in chiral multilayers from the shrinking or fission of elongated stripe textures. Here we report an experimental and theoretical study of the temperature dependence of this stripe-toskyrmion transition in Co/Pt-based multilayers. Field-reversal magnetometry and Lorentz microscopy experiments over 100???350 K establish the increased efficacy of stripe-to-skyrmion fission at higher temperatures???driven primarily by the thermal evolution of key magnetic interactions???which enhances the resulting skyrmion density. Atomistic calculations elucidate that the energy barrier to fission governs the thermodynamics of skyrmion formation. Our results establish a mechanistic picture of the stripe-to-skyrmion transition and advance the use of thermal knobs for efficient skyrmion generation.