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arXiv · 2304.11778

Observation of colossal topological Hall effect in noncoplanar ferromagnet Cr5Te6 thin films

Abstract

The topological Hall effect (THE) is critical to the exploration of the spin chirality generated by the real-space Berry curvature, which has attracted worldwide attention for its prospective applications in spintronic devices. However, the prominent THE remains elusive at room temperature, which severely restricts the practical integration of chiral spin textures. Here, we show a colossal intrinsic THE in large-area ferromagnet Cr5Te6 thin films epitaxially grown by pulsed laser deposition. Such a THE can be maintained until 270 K, which is attributed to the field-stimulated noncoplanar spin textures induced by the interaction of the in-plane ferromagnet and antiferromagnet infrastructures. Our first-principles calculations further verify the considerable Dzyaloshinskii-Moriya interaction in Cr5Te6. This work not only paves the way for robust chiral spin textures near room temperature in large-area low-dimensional ferromagnetic films for practical applications, but also facilitates the development of high-density and dissipationless spintronic devices.

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Yequan Chen, Yingmei Zhu, Renju Lin, Wei Niu, Ruxin Liu, Wenzhuo Zhuang, Xu Zhang, Jinghua Liang, Wenxuan Sun, Zhongqiang Chen, Yongsheng Hu, Fengqi Song, Jian Zhou, Di Wu, Binghui Ge, Hongxin Yang, Rong Zhang, Xuefeng Wang. 2023-04-24. Observation of colossal topological Hall effect in noncoplanar ferromagnet Cr5Te6 thin films. https://doi.org/10.1002/adfm.202302984

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