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arXiv · 2504.20540

Spin Wave Dispersion of the van der Waals Antiferromagnet NiPS$_3$

Ritesh Das·Rob den Teuling·Artem V. Bondarenko·Elena V. Tartakovskaya·Gerrit E. W. Bauer·Jaime Ferrer·Yaroslav M. Blanter
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Abstract

We calculate the magnon dispersion spectra of the two-dimensional zigzag van der Waals antiferromagnet NiPS$_3$ for monolayer, bilayer, and bulk systems as a function of an external magnetic field. We calculate the exchange and anisotropy constants in our spin model by first principles. We can accurately explain the transition from a collinear to a canted ground state for a magnetic field applied normal to the (in-plane) easy-axis, and a spin-flop transition when the field is parallel to it. A topologically protected Dirac nodal line is present and robust with respect to both external and anisotropy fields.

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Ritesh Das, Rob den Teuling, Artem V. Bondarenko, Elena V. Tartakovskaya, Gerrit E. W. Bauer, Jaime Ferrer, Yaroslav M. Blanter. 2025-04-29. Spin Wave Dispersion of the van der Waals Antiferromagnet NiPS$_3$. https://doi.org/10.1063/5.0312007

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