The concept of topology has dramatically expanded the research landscape of magnetism, leading to the discovery of numerous magnetic textures with intriguing topological properties. A magnetic skyrmion is an emergent topological magnetic texture with a string-like structure in three dimensions and a disk-like structure in one and two dimensions. Skyrmions in zero dimensions have remained elusive due to challenges from many competing orders. Here, by combining electron holography and micromagnetic simulations, we uncover the real-space magnetic configurations of a skyrmionic vortex structure confined in a B20-type FeGe tetrahedral nanoparticle. An isolated skyrmionic vortex forms at the ground state and this texture shows excellent robustness against temperature without applying a magnetic field. Our findings shed light on zero-dimensional geometrical confinement as a route to engineer and manipulate individual skyrmionic metastructures.
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K.N. was supported by a Grant-in-Aid for Scientific Research (B) (number 19H02418) and for Challenging Research (Exploratory) (number 19K22052) from the JSPS. X.Y. was supported by a Grant-in-Aid for Scientific Research (A) (number 19H00660) from the JSPS and JST CREST (grant number JPMJCR20T1). N.N. was supported by JST CREST (grant number JPMJCR1874). A.C.B. and J.Z. acknowledge support from the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES) under award number DE-SC0020221. Y.L. was supported by the Special Postdoctoral Researcher programme of RIKEN. N.M., M.J.S. and S.J. were supported by US NSF grant ECCS-1609585. M.J.S. also acknowledges support from the NSF Graduate Research Fellowship Program.
The authors declare no competing interests.
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Supplementary notes 1–5, references 1–7, Figs. 1–22 and captions of Movies 1–4.
Simulated 3D view of the skyrmionic vortex in a 145 nm tetrahedron (in-plane (xy plane) magnetic component).
Simulated 3D view of the skyrmionic vortex in a 145 nm tetrahedron (out-of-plane (z axis) magnetic component).
Sliced vector plots of the skyrmionic vortex in a 145 nm tetrahedron.
Sliced vector plots of the skyrmionic vortex in a 185 nm tetrahedron.
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Niitsu, K., Liu, Y., Booth, A.C. et al. Geometrically stabilized skyrmionic vortex in FeGe tetrahedral nanoparticles. Nat. Mater. 21, 305–310 (2022). https://doi.org/10.1038/s41563-021-01186-x
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