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arXiv · 2007.05939

Three-Dimensional Chiral Magnetization Structures in FeGe Nanospheres

Swapneel Amit Pathak·Riccardo Hertel
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Abstract

Skyrmions, spin spirals, and other chiral magnetization structures developing in materials with intrinsic Dzyaloshinsky-Moriya Interaction display unique properties that have been the subject of intense research in thin-film geometries. Here we study the formation of three-dimensional chiral magnetization structures in FeGe nanospheres by means of micromagnetic finite-element simulations. In spite of the deep sub-micron particle size, we find a surprisingly large number of distinct equilibrium states, namely, helical, meron, skyrmion, chiral-bobber and quasi-saturation state. The distribution of these states is summarized in a phase diagram displaying the ground state as a function of the external field and particle radius. This unusual multiplicity of possible magnetization states in individual nanoparticles could be a useful feature for multi-state memory devices. We also show that the magneto-dipolar interaction is almost negligible in these systems, which suggests that the particles could be arranged at high density without experiencing unwanted coupling.

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Swapneel Amit Pathak, Riccardo Hertel. 2020-07-12. Three-Dimensional Chiral Magnetization Structures in FeGe Nanospheres. https://doi.org/10.1103/physrevb.103.104414

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