Laser-induced metastable (anti-)skyrmion states with higher-order topological charge

Tim Titze; Marcel Möller; Timo Schmidt; Mariam Hassan; Sabri Koraltan; Stefan Mathias; Manfred Albrecht; Claus Ropers; Daniel Steil

arXiv · 2609.13112

Laser-induced metastable (anti-)skyrmion states with higher-order topological charge

Tim Titze·Marcel Möller·Timo Schmidt·Mariam Hassan·Sabri Koraltan·Stefan Mathias·Manfred Albrecht·Claus Ropers·Daniel Steil

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Abstract

Ultrafast creation and manipulation of topologically non-trivial spin objects promises significant potential for spintronic applications. Here, we demonstrate laser-induced nucleation of skyrmions and antiskyrmions with topological charge up to $|Q|=3$ from the saturated magnetization state of a Co/Ni-multilayer which does not intrinsically host a skyrmionic ground state. The resulting configuration of spin objects thus constitutes a metastable, thermodynamically hidden magnetic state. We control the number and type of spin objects by the excitation fluence and the external out-of-plane magnetic field.

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Tim Titze, Marcel Möller, Timo Schmidt, Mariam Hassan, Sabri Koraltan, Stefan Mathias, Manfred Albrecht, Claus Ropers, Daniel Steil. 2026-09-11. Laser-induced metastable (anti-)skyrmion states with higher-order topological charge. https://arxiv.org/abs/2609.13112

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