Börge GÖBEL
Magnetic skyrmions have attracted enormous research interest since their discovery a decade ago. Especially the non-trivial real-space topology of these nano-whirls leads to fundamentally interesting and technologically relevant effects – the skyrmion Hall effect of the texture and the topological Hall effect of the electrons. Furthermore, it grants skyrmions in a ferromagnetic surrounding great stability even at small sizes, making skyrmions aspirants to become the carriers of information in the future. Still, the utilization of skyrmions in spintronic devices has not been achieved yet, among others, due to shortcomings in their current-driven motion.
In this talk, we present recent trends in the field of topological spin textures that go beyond skyrmions [1]. We discuss magnetic antiskyrmions [2], bimerons [3], antiferromagnetic skyrmions [4] and hopfions [5]. These objects exhibit advantageous emergent electrodynamic effects compared to skyrmions, either due to their lower symmetry or due to a compensated topological charge. A special focus is on antiskyrmions in Heuslers. We show via simulations, Lorentz transmission electron microscopy measurements and Hall transport measurements [2,6,7] that skyrmions, antiskyrmion and topologically trivial bubbles [8] can coexist in such materials. They can even appear fractionally near the sample’s edges [9].
[2] J. Jena*, B. Göbel*, T. Ma, V. Kumar, R. Saha, I. Mertig, C. Felser, S. Parkin. Nature Communications 11, 1115 (2020)
[3] B. Göbel, A. Mook, J. Henk, I. Mertig, O. Tretiakov. Phys. Rev. B. 99, 060407(R) (2019)
[4] B. Göbel, A. Mook, J. Henk, I. Mertig. Phys. Rev. B. 96, 060406(R) (2017)
[5] B. Göbel, C. Akosa, G. Tatara, I. Mertig. Phys. Rev. Research 2, 013315 (2020)
[6] J. Jena*, B. Göbel*, V. Kumar, I. Mertig, C. Felser, S. Parkin. Science Advances 6, eabc0723 (2020)
[7] P. Sivakumar, B. Göbel, E. Lesne, A. Markou, J. Gidugu, J. Taylor, H. Deniz, J. Jena, C. Felser, I. Mertig, S. Parkin. ACS Nano 14, 13463 (2020)
[8] B. Göbel, I. Mertig. Phys. Rev. Applied 15, 064052 (2021)
[9] J. Jena, B. Göbel, T. Hirosawa, S. Díaz, T. Hinokihara, V. Kumar, I. Mertig, C. Felser, S. Parkin. Research Square preprint: DOI: 10.21203/rs.3.rs-136696/v1