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arXiv · 2607.25418

Imaging the Néel Vector in Two-Dimensional Antiferromagnets using Antisymmetric Compton Scattering

Wuxuan Li·Zhuocheng Lu·Jingshan Qi·Hua Wang·Kai Chang
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Abstract

We demonstrate that antisymmetric Compton scattering can detect both the switching and the continuous rotation of the Néel vector in two-dimensional (2D) antiferromagnets. By probing magnetoelectric (ME) multipoles, which couple electric and magnetic dipoles, this approach overcomes the limitations of conventional techniques that rely on a finite net magnetization. Using a group-theoretical decomposition of the staggered moments in 2D MnPS$_3$ into irreducible representations, combined with first-principles calculations, we show that the antisymmetric Compton profile (ACP) is highly sensitive to the Néel vector orientation: it reverses sign under Néel vector reversal and exhibits distinct anisotropies under in-plane rotation. These results establish the ACP as a versatile probe of antiferromagnetic (AFM) order and magnetoelectric phenomena in van der Waals materials.

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Wuxuan Li, Zhuocheng Lu, Jingshan Qi, Hua Wang, Kai Chang. 2026-07-28. Imaging the Néel Vector in Two-Dimensional Antiferromagnets using Antisymmetric Compton Scattering. https://arxiv.org/abs/2607.25418

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