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arXiv · 2403.17354

Large topological Hall effect arising from spin reorientation in kagome magnet Fe3Ge

Abstract

Materials systems with spin chirality can provide ultra-high-density, ultra-fast, and ultralow-power information carriers for digital transformation. These material systems include magnetic skyrmions, chiral domain walls, spin reorientation,and so on. The topological Hall effect (THE) has been identified as the most convenient and effective tool for detecting the presence of spin chirality in these systems. The research on the THE that may arise from spin reorientation and specifically in Fe3Ge with spin reorientation remains an unexplored area, so we study the THE in Fe3Ge Conduct systematic research. X-Ray Diffraction (XRD) results indicate that our Fe3Ge ribbon sample has a D019 structure. First-principles calculations and magnetic and electrical testing confirm spin reorientation in the Fe3Ge ribbon sample at 350 K.The Hall resistivity test results are consistent with our expectations, indicating the presence of the THE in the Fe3Ge ribbon sample. The topological Hall resistivity reaches a maximum value of 0.69 mΩ cm at 400 K. For the first time, a detailed experimental study of the THE in Fe3Ge with spin reorientation has been conducted, introducing a new member to the family of THE.

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Zixuan Zhang, Mingyue Zhao, Li Ma, Guoke Li, Congmian Zhen, Dewei Zhao, Denglu Hou. 2024-03-26. Large topological Hall effect arising from spin reorientation in kagome magnet Fe3Ge. https://arxiv.org/abs/2403.17354

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