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arXiv · 1912.11228

Observation of Magnetic Skyrmion Bubbles in a van der Waals ferromagnet Fe3GeTe2

Bei Ding·Zefang Li·Guizhou Xu·Hang Li·Zhipeng Hou·Enke Liu·Xuekui Xi·Feng Xu·Yuan Yao·Wenhong Wang
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Abstract

Two-dimensional (2D) van der Waals (vdW) magnetic materials have recently been introduced as a new horizon in materials science and enable the potential applications for next-generation spintronic devices. Here, in this communication, the observations of stable Bloch-type magnetic skyrmions in single crystals of 2D vdW Fe3GeTe2 (FGT) are reported by using in-situ Lorentz transmission electron microscopy (TEM). We find the ground-state magnetic stripe domains in FGT transform into skyrmion bubbles when an external magnetic field is applied perpendicularly to the (001) thin plate with temperatures below the Curie-temperature TC. Most interestingly, a hexagonal lattice of skyrmion bubbles is obtained via field cooling manipulation with magnetic field applied along the [001] direction. Owing to their topological stability, the skyrmion bubble lattices are stable to large field-cooling tilted angles and further reproduced by utilizing the micromagnetic simulations. These observations directly demonstrate that the 2D vdW FGT possesses a rich variety of topological spin textures, being of a great promise candidate for future applications in the field of spintronics.

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Bei Ding, Zefang Li, Guizhou Xu, Hang Li, Zhipeng Hou, Enke Liu, Xuekui Xi, Feng Xu, Yuan Yao, Wenhong Wang. 2019-12-24. Observation of Magnetic Skyrmion Bubbles in a van der Waals ferromagnet Fe3GeTe2. https://doi.org/10.1021/acs.nanolett.9b03453

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