Topological and Planar Hall Effect in Monoclinic van der Waals Ferromagnet NbFeTe$_2$

Suchanda Mondal; Shubhankar Roy; Poulami Manna; Ravi Prakash Singh

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arXiv · 2602.07611

Topological and Planar Hall Effect in Monoclinic van der Waals Ferromagnet NbFeTe$_2$

Suchanda Mondal·Shubhankar Roy·Poulami Manna·Ravi Prakash Singh

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Abstract

Two-dimensional (2D) van der Waals (vdW) ferromagnets have emerged as a critical class of quantum materials for next-generation, low-dimensional spintronic devices. In this study, we report a comprehensive study of the transport properties of the layered soft ferromagnet $\text{NbFeTe}_2$. We report the first observation of the topological Hall effect (THE) and the planar Hall effect (PHE) in metallic $\text{NbFeTe}_2$. THE signatures persist up to 45 K, while PHE remains evident well above Curie temperature ($T_C$). The observed negative longitudinal magnetoresistance, along with the PHE, provides strong evidence for a nontrivial electronic band structure. The coexistence of perpendicular magnetic anisotropy and a substantial THE: two key properties that are highly desirable for future spintronics applications, makes monoclinic vdW ferromagnetic $\text{NbFeTe}_2$ a promising platform to advance spintronics applications.

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Suchanda Mondal, Shubhankar Roy, Poulami Manna, Ravi Prakash Singh. 2026-02-07. Topological and Planar Hall Effect in Monoclinic van der Waals Ferromagnet NbFeTe$_2$. https://arxiv.org/abs/2602.07611

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