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The following publications are listed in the online university bibliography of the University of Duisburg-Essen. Further information may also be found on the person's personal web pages.

Topologically nontrivial textures are promising candidates as information units in future data manipulation and storage devices, as well as in unconventional computing such as reservoir computing. In two dimensions, an example of such a texture is the magnetic skyrmion. In my PhD so far, I have investigated the current-driven creation and dynamics of skyrmions in the cycloidal state of a magnet, in which a skyrmion typically has a higher speed in response to a given driving current than in the ferromagnetic state. [Knapman, R. et. al., J. Phys. D: Appl. Phys. 54, 404003 (2021)]

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A schematic of a H-shaped skyrmion in the cycloidal state of a ferromagnet.

Another magnetic texture of interest is the magnetic hopfion, which can be thought of as skyrmion tube for which one end has been rotated through 360° and the ends glued together. As such, this object is defined in a bulk system, as opposed to a skyrmion, which can be realised in thin films. The topology of such a structure is defined through the linking of so-called preimages, which are all the points in the texture in which the magnetization points in a given direction. As part of my PhD, I aim to investigate methods of creating and stabilising magnetic hopfions in ferromagnets.

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Various preimages of a hopfion where the z-component of magnetization is zero; the topological nontriviality comes from their interlinking.
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