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arXiv · 2608.14189

Probing intrinsic magnetic phases in low-dimensional nearly twin-free NiPS$_3$ single crystals

Abstract

We report the intrinsic thermal and magnetic properties of the low-dimensional van der Waals (vdW) antiferromagnet NiPS$_3$ and explore its emergent magnetic phases by controlling crystallographic twinning. Using nearly twin-free crystals, we resolve intrinsic properties that are typically obscured by multidomain effects in bulk samples. Magnetization results reveal a highly anisotropic, sharp spin-flop transition, confirming the high domain purity of our crystals. Furthermore, high-precision thermodynamic and transport data reveal a broad fluctuation regime around the N\'eel temperature ($T_{\mathrm{N}}$ = 157.5 K), with a heat capacity anomaly and a concurrent suppression of thermal conductivity. Field-dependent thermal transport shows a small but distinct contribution from spin-lattice coupling, as evidenced by the dip at the spin-flop transition. We develop a theoretical model to explain these properties reported in this paper, with good agreement between experiment and theory. Our work establishes a definitive baseline for bulk properties of NiPS$_3$ and demonstrates the feasibility of resolving intrinsic anisotropies by addressing crystallographic twinning in vdW magnets.

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Yeochan An, Heejun Yang, Sung Jin Park, Giung Park, Woonghee Cho, Pyeongjae Park, Seokhwan Yun, Yoshimitsu Kohama, Je-Geun Park. 2026-08-14. Probing intrinsic magnetic phases in low-dimensional nearly twin-free NiPS$_3$ single crystals. https://arxiv.org/abs/2608.14189

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