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Description
In non-centrosymmetric crystal structures with $D_{2d}$ or $S_4$ symmetry, anisotropic Dzyaloshinskii-Moriya interaction (DMI) stabilizes antiskyrmions which was recently confirmed experimentally [1,2]. In these materials, easy-axis anisotropy additionally stabilizes skyrmions and non-topological bubbles in certain ranges of external magnetic fields and lamella thicknesses. The competition between magnetic dipolar interaction and DMI renders skyrmions elliptical depending on their handedness. Also, dipolar interaction stabilizes skyrmion caps on top of antiskyrmions which renders them rectangular [3]. In this work, we investigate how external mechanical strain can be used as an additional tuning parameter for the stability of these topological magnetic textures. We show that strain breaks the degeneracy of distinct types of elongated skyrmions and antiskyrmions. This can be used to controllably switch the direction of elongation of hybrid antiskyrmion with hysteresis.
References:
[1] A. Nayak et al., ‘Magnetic antiskyrmions above room temperature in tetragonal Heusler materials’, Nature 548, 561-566 (2017).
[2] K. Karube, L. C. Peng, J. Masell, et al., ‘Room-temperature antiskyrmions and sawtooth surface textures in a non-centrosymmetric magnet with S4 symmetry’, Nat. Mater. 20, 335-340 (2021).
[3] F. S. Yasin, J. Masell et al., ‘Bloch Point Quadrupole Constituting Hybrid Topological Strings Revealed with Electron Holographic Vector Field Tomography’, Adv. Mater. 36 (16), 2311737 (2024).
