Designing Optimal Distorted-Octahedra Superlattices for Strong Topological Hall Effect

Yiyan Fan; Qinghua Zhang; Jingdi Lu; Chuanrui Huo; Tianyang Wang; Qiao Jin; Ting Cui; Qianying Wang; Dongke Rong; Shiqing Deng; Lingfei Wang; Kuijuan Jin; Jun Chen; Er-Jia Guo

arXiv · 2504.15563

Designing Optimal Distorted-Octahedra Superlattices for Strong Topological Hall Effect

Yiyan Fan·Qinghua Zhang·Jingdi Lu·Chuanrui Huo·Tianyang Wang·Qiao Jin·Ting Cui·Qianying Wang·Dongke Rong·Shiqing Deng·Lingfei Wang·Kuijuan Jin·Jun Chen·Er-Jia Guo

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Abstract

Topologically protected spin states hold great promise for applications in next generation of memory circuits and spintronic devices. These intriguing textures typically emerge in bulk materials or heterostructures with broken inversion symmetry, accompanied by an enhanced Dzyaloshinskii-Moriya interaction (DMI). In this study, we successfully induced the topological Hall effect (THE) in atomically designed (DyScO3)n/(SrRuO3)n (DnSn) superlattices over a significant range of temperatures (10~120K) and thicknesses (16~40nm). Using magnetic force microscopy (MFM), we observed the formation and stability of magnetic domains, such as topological skyrmions. By precisely controlling the interlayer thickness (n) and biaxial strain, we elucidated the mechanisms underlying the modulation and induction of magnetic topological states. Supporting evidence was provided by scanning transmission electron microscopy (STEM) and X-ray absorption spectroscopy (XAS), thereby lending further credence to our conclusions. These heterostructures offer a universal method for exploring topological phenomena driven by distorted octahedra, while enhancing the integrability and addressability of topologically protected functional devices.

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Yiyan Fan, Qinghua Zhang, Jingdi Lu, Chuanrui Huo, Tianyang Wang, Qiao Jin, Ting Cui, Qianying Wang, Dongke Rong, Shiqing Deng, Lingfei Wang, Kuijuan Jin, Jun Chen, Er-Jia Guo. 2025-04-22. Designing Optimal Distorted-Octahedra Superlattices for Strong Topological Hall Effect. https://arxiv.org/abs/2504.15563

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