Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet Fe3-xGaTe2 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

doi:10.1038/s41467-024-45310-2

Room-temperature sub-100 nm Néel-type skyrmions in non-stoichiometric van der Waals ferromagnet Fe_3-xGaTe₂ with ultrafast laser writability

Nat Commun. 2024 Feb 3;15(1):1017. doi: 10.1038/s41467-024-45310-2.

Authors

Zefang Li^#¹, Huai Zhang^#², Guanqi Li^#³, Jiangteng Guo¹, Qingping Wang⁴, Ying Deng¹, Yue Hu¹, Xuange Hu¹, Can Liu¹, Minghui Qin², Xi Shen⁵, Richeng Yu⁵, Xingsen Gao², Zhimin Liao⁶, Junming Liu^{2

7}, Zhipeng Hou⁸, Yimei Zhu⁹, Xuewen Fu^{10

11}

Affiliations

¹ Ultrafast Electron Microscopy Laboratory, The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin, China.
² Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, China.
³ School of Integrated Circuits, Guangdong University of Technology, Guangzhou, China.
⁴ School of Physics and Electronic and Electrical Engineering, Aba Teachers University, Wenchuan, China.
⁵ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
⁶ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, China.
⁷ Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
⁸ Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, China. houzp@m.scnu.edu.cn.
⁹ Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York, USA. zhu@bnl.gov.
¹⁰ Ultrafast Electron Microscopy Laboratory, The MOE Key Laboratory of Weak-Light Nonlinear Photonics, School of Physics, Nankai University, Tianjin, China. xwfu@nankai.edu.cn.
¹¹ School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin, China. xwfu@nankai.edu.cn.

^# Contributed equally.

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 Fe₃GaTe₂ 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 Fe_3-xGaTe₂ using a single femtosecond laser pulse. Our results manifest the Fe_3-xGaTe₂ as a promising building block for realizing skyrmion-based magneto-optical functionalities.