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arXiv · 2402.13770

Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet $\rm Fe_{3-x}GaTe_{2}$ with ultrafast laser writability

Zefang Li·Huai Zhang·Guanqi Li·Jiangteng Guo·Qingping Wang·Ying Deng·Yue Hu·Xuange Hu·Can Liu·Minghui Qin·Xi Shen·Richeng Yu·Xingsen Gao·Zhimin Liao·Junming Liu·Zhipeng Hou·Yimei Zhu·Xuewen Fu
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Abstract

Realizing room-temperature magnetic skyrmions in two-dimensional van der Waals ferromagnets offers unparalleled prospects for future spintronic applications. However, due to the intrinsic spin fluctuations that suppress atomic long-range magnetic order and the inherent inversion crystal symmetry that excludes the presence of the Dzyaloshinskii-Moriya interaction, achieving room-temperature skyrmions in 2D magnets remains a formidable challenge. In this study, we target room-temperature 2D magnet $\rm Fe_3GaTe_2$ and unveil that the introduction of iron-deficient into this compound enables spatial inversion symmetry breaking, thus inducing a significant Dzyaloshinskii-Moriya interaction that brings about room-temperature Néel-type skyrmions with unprecedentedly small size. To further enhance the practical applications of this finding, we employ a homemade in-situ optical Lorentz transmission electron microscopy to demonstrate ultrafast writing of skyrmions in $\rm Fe_{3-x}GaTe_2$ using a single femtosecond laser pulse. Our results manifest the $\rm Fe_{3-x}GaTe_2$ as a promising building block for realizing skyrmion-based magneto-optical functionalities.

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Zefang Li, Huai Zhang, Guanqi Li, Jiangteng Guo, Qingping Wang, Ying Deng, Yue Hu, Xuange Hu, Can Liu, Minghui Qin, Xi Shen, Richeng Yu, Xingsen Gao, Zhimin Liao, Junming Liu, Zhipeng Hou, Yimei Zhu, Xuewen Fu. 2024-02-21. Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet $\rm Fe_{3-x}GaTe_{2}$ with ultrafast laser writability. https://doi.org/10.1038/s41467-024-45310-2

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