Abstract
Recently resynthesized FeNbTe2 has been confirmed to exhibit ferromagnetism. Using first-principles methods, we investigate the magnetic properties of two-dimensional FeXZ2 (X = Nb, Ta; Z = S, Se, Te) compounds, including their non-centrosymmetric Janus counterparts. These materials are found to be energetically, dynamically, thermally, and mechanically stable, indicating that FeNbTe2 can be exfoliated and that new related compounds could be realized experimentally. Analysis of hopping parameters reveals that nearest-neighbor magnetic interactions are primarily direct, while second-nearest and more distant interactions are mediated by chalcogen atoms. Despite their smaller magnitude, second-nearest interactions play a decisive role in magnetic ordering. We identify canted magnetic anisotropy with strong magnetocrystalline anisotropy energy and easy-axis tilts of up to 41∘, an uncommon feature favorable for spintronics. Monte Carlo simulations yield Curie temperatures below room temperature, while micromagnetic simulations predict that Janus FeNbSeTe can host zero-field Néel-type skyrmions, making it a promising target for experiments.
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Data availability
All significant results are presented in the main manuscript and supplementary materials. Additional data supporting this study are available from the corresponding author upon reasonable request. Code availability: For our DFT calculations, we employed VASP, QuantumATK, Wannier90, TB2J, USPEX, and Phonopy. Monte Carlo and micromagnetic simulations were conducted using UppASD and Mumax. All these software packages are either commercially available or open-source.
Code availability
For our DFT calculations, we employed VASP, QuantumATK, Wannier90, TB2J, USPEX, and Phonopy. Monte Carlo and micromagnetic simulations were conducted using UppASD and Mumax. All these software packages are either commercially available or open-source.
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Acknowledgements
B.S. acknowledges financial support from the Swedish Research Council (grant no. 2022-04309 and grant No. 2018-07082). The computations were enabled by resources provided by the National Academic Infrastructure for Supercomputing in Sweden (NAISS) at UPPMAX (NAISS 2024/5-258) and at NSC and PDC (NAISS 2024/3-40), partially funded by the Swedish Research Council through grant agreement no. 2022-06725. B.S. and S. E. also acknowledge EuroHPC for awarding us access to EHPC-DEV-2024D03-043 hosted by LUMI in Finland, and EU2023D11-039 hosted by Karolina at IT4Innovations, Czech Republic. Artificial intelligence was used to improve the language and readability of this work.
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S.E.: Investigation (lead); Data curation (lead); Formal analysis (lead); Visualization (lead); Writing—original draft (lead). N.M.: Data curation (supporting); Formal analysis (supporting); Writing—review and editing (supporting). A.M.: Formal analysis (supporting). V.B.: Formal analysis (supporting). O.E.: Formal analysis (supporting). B.S.: Resources (lead); Formal analysis (supporting); Methodology (lead); Writing—review and editing (lead); Funding acquisition (lead); Supervision (lead). All authors reviewed the manuscript.
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Ershadrad, S., Machacova, N., Mukherjee, A. et al. Complex magnetic exchange, anisotropy and skyrmionic textures in 2D ferromagnets with transition metals and chalcogens. npj 2D Mater Appl (2026). https://doi.org/10.1038/s41699-026-00691-4
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DOI: https://doi.org/10.1038/s41699-026-00691-4
