Controlled\nSeparation of Skyrmions and Antiskyrmions\nby Kitaev Interaction

As topological quasi-particles in magnetic materials,\nskyrmions\nand antiskyrmions show potential in spintronics for information storage\nand computing. However, effectively controlling and separating these\nentities remain significantly challenging. Here, we demonstrate that\nanisotropic Kitaev exchange can distinctly influence the static and\ndynamic behaviors for skyrmions and antiskyrmions, thus aiding their\nmanipulation and separation. Employing the monolayer frustrated magnet\nNiBr<sub>2</sub> as a model system, we construct a magnetic field–strain\nphase diagram to explore the strain-controlled stability of these\ntopological structures. The introduction of the Kitaev term breaks\nthe energy degeneracy among magnetic structures with various helicities,\nleading to a translation–rotation mode transition with an increase\nin current. Importantly, due to their different rotational symmetries,\nthe skyrmion and antiskyrmion show distinct critical behaviors and\nrotational dynamics, which are governed by the Kitaev parameters.\nThese phenomena enable the design of two proof-of-concept spintronics\ndevices, i.e., a skyrmion separator and a non-gate logic unit.