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arXiv · 2212.00931

Inducing Skyrmion Flop Transitions in Co$_8$Zn$_8$Mn$_4$ at Room Temperature

Simon A. Meynell·Yolita M. Eggeler·Joshua D. Bocarsly·Daniil A. Kitchaev·Bailey E. Rhodes·Tresa M. Pollock·Stephen D. Wilson·Anton Van der Ven·Ram Seshadri·Marc De Graef·Ania Bleszynski Jayich·Daniel S. Gianola
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Abstract

Magnetic skyrmions are topologically-protected spin textures that manifest in certain non-centrosymmetric ferromagnets under the right conditions of temperature and field. In thin film skyrmion hosts, demagnetization effects combined with geometric confinement can result in two distinct types of spin textures: those with their axis of symmetry in the plane of the film (IP) and those with their axis pointing out-of-plane (OOP). Here we present Lorentz transmission electron microscopy evidence in conjunction with numerical modeling showing a flop transition between IP and OOP skyrmions in Co$_8$Zn$_8$Mn$_4$ at room temperature. We show that this skyrmion flop transition is controllable via the angle of the external field relative to the film normal and we illustrate how this transition depends on thickness. Finally, we propose a skyrmion-writing device that utilizes the details of this transition.

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Simon A. Meynell, Yolita M. Eggeler, Joshua D. Bocarsly, Daniil A. Kitchaev, Bailey E. Rhodes, Tresa M. Pollock, Stephen D. Wilson, Anton Van der Ven, Ram Seshadri, Marc De Graef, Ania Bleszynski Jayich, Daniel S. Gianola. 2022-12-02. Inducing Skyrmion Flop Transitions in Co$_8$Zn$_8$Mn$_4$ at Room Temperature. https://doi.org/10.1103/physrevmaterials.7.044401

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