Dipolar skyrmions and antiskyrmions of arbitrary topological charge at room temperature

Magnetic skyrmions are localized, stable topological magnetic textures that behave like particle-like excitations under external stimuli. Efficient control of their motion using spin-polarized currents has enabled skyrmion-based device concepts. The coexistence of skyrmions with high topological charge promises enhanced functionalities. Here, we directly observe dipolar skyrmions and antiskyrmions with arbitrary topological charge in Co/Ni multilayers at room temperature. We find dipolar-stabilized spin objects with topological charges up to 10, characterize their nucleation process, quantify the energy dependence on topological charge, and assess the effects of material parameters on stability. Micromagnetic simulations further demonstrate spin-transfer-torque-driven motion of these textures, relevant for device applications.

Mariam Hassan, Sabri Koraltan, Aladin Ullrich, Florian Bruckner, Rostyslav O. Serha, Khrystyna V. Levchenko, Gaspare Varvaro, Nikolai S. Kiselev, Michael Heigl, Claas Abert, Dieter Suess, Manfred Albrecht