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arXiv · 2510.20181

Domain wall induced topological Hall effect in the chiral-lattice ferromagnet Fe$_x$TaS$_2$

Sk Jamaluddin·Warit Nisaiyok·Yu Zhang·Hari Bhandari·Brian A. Francisco·Peter E. Siegfried·Fehmi Sami Yasin·Tianyi Wang·Abhijeet Nayak·Mohamed El Gazzah·Resham Babu Regmi·June Ho Yeo·Liuyan Zhao·J. F. Mitchell·Yong-Tao Cui·Nirmal J. Ghimire
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Abstract

Magnetic topology and its associated emergent phenomena are central to realizing intriguing quantum states and spintronics functionalities. Designing spin textures to achieve strong and distinct electrical responses remains a significant challenge. Layered transition metal dichalcogenides offer a versatile platform for tailoring structural and magnetic properties, enabling access to a wide spectrum of topological magnetic states. Here, we report a domain-wall-driven, large, and tunable topological Hall effect (THE) in a non-centrosymmetric intercalated transition metal dichalcogenides series Fe$_x$TaS$_2$. By systematically varying the Fe intercalation level, we exert precise control over the magnetic ground states, allowing manipulation of the topological Hall effect. Real-space magnetic force microscopy (MFM) provides direct evidence of periodic magnetic stripe domain formation, confirming the microscopic origin of the observed topological transport phenomena. Our findings establish a promising way for tuning the topology of domains to generate substantial electromagnetic responses in layered magnetic materials.

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Sk Jamaluddin, Warit Nisaiyok, Yu Zhang, Hari Bhandari, Brian A. Francisco, Peter E. Siegfried, Fehmi Sami Yasin, Tianyi Wang, Abhijeet Nayak, Mohamed El Gazzah, Resham Babu Regmi, June Ho Yeo, Liuyan Zhao, J. F. Mitchell, Yong-Tao Cui, Nirmal J. Ghimire. 2025-10-23. Domain wall induced topological Hall effect in the chiral-lattice ferromagnet Fe$_x$TaS$_2$. https://arxiv.org/abs/2510.20181

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