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arXiv · 2304.01369

Three-Dimensional Structure of Hybrid Magnetic Skyrmions Determined by Neutron Scattering

Abstract

Magnetic skyrmions are topologically protected chiral spin textures which present opportunities for next-generation magnetic data storage and logic information technologies. The topology of these structures originates in the geometric configuration of the magnetic spins - more generally described as the structure. While the skyrmion structure is most often depicted using a 2D projection of the three-dimensional structure, recent works have emphasized the role of all three dimensions in determining the topology and their response to external stimuli. In this work, grazing-incidence small-angle neutron scattering and polarized neutron reflectometry are used to determine the three-dimensional structure of hybrid skyrmions. The structure of the hybrid skyrmions, which includes a combination of Néel-like and Bloch-like components along their length, is expected to significantly contribute to their notable stability, which includes ambient conditions. To interpret the neutron scattering data, micromagnetic simulations of the hybrid skyrmions were performed, and the corresponding diffraction patterns were determined using a Born approximation transformation. The converged magnetic profile reveals the magnetic structure along with the skyrmion depth profile, including the thickness of the Bloch and Néel segments and the diameter of the core.

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WLNC Liyanage, Nan Tang, Lizabeth Quigley, Julie A. Borchers, Alexander J. Grutter, Brian B. Maranville, Sunil K. Sinha, Nicolas Reyren, Sergio A. Montoya, Eric E. Fullerton, Lisa DeBeer-Schmitt, Dustin A. Gilbert. 2023-04-19. Three-Dimensional Structure of Hybrid Magnetic Skyrmions Determined by Neutron Scattering. https://doi.org/10.1103/physrevb.107.184412

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