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arXiv · 2305.02028

Large anomalous Hall effect and unusual domain switching in an orthorhombic antiferromagnetic material NbMnP

Abstract

Specific antiferromagnetic (AF) spin configurations generate large anomalous Hall effects (AHEs) even at zero magnetic field through nonvanishing Berry curvature in momentum space. In addition to restrictions on AF structures, suitable control of AF domains is essential to observe this effect without cancellations among its domains; therefore, compatible materials remain limited. Here we show that an orthorhombic noncollinear AF material, NbMnP, acquired AF structure-based AHE and controllability of the AF domains. Theoretical calculations indicated that a large Hall conductivity of $\sim230$ $\Omega^{-1}$cm$^{-1}$ originated from the AF structure of NbMnP. Symmetry considerations explained the production of a small net magnetization, whose anisotropy enabled the generation and cancellation of the Hall responses using magnetic fields in different directions. Finally, asymmetric hysteresis in NbMnP shows potential for development of controllability of responses in AF materials.

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Hisashi Kotegawa, Yoshiki Kuwata, Vu Thi Ngoc Huyen, Yuki Arai, Hideki Tou, Masaaki Matsuda, Keiki Takeda, Hitoshi Sugawara, Michi-To Suzuki. 2023-05-03. Large anomalous Hall effect and unusual domain switching in an orthorhombic antiferromagnetic material NbMnP. https://doi.org/10.1038/s41535-023-00587-2

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