近日，法国巴黎萨克雷大学Paul McClarty团队报道了MnF2中的极化中子揭示交错磁性。这一研究成果发表在2026年10月29日出版的《科学》杂志上。

交错磁体是一类具有对称性强制自旋劈裂能带的补偿磁体。学界已在多种材料中发现了支持其存在的直接谱学实验证据。例如，非弹性中子散射（INS）近期用于见证MnTe中与交错磁性相符的磁振子能带劈裂。

研究组给出MnF2的极化INS测量结果，证明MnF2属于交错磁体。实验数据揭示，该能带劈裂源于长程偶极耦合。此外，借助畴偏置样品，研究数据揭示了中子散射截面中的非零手性，且两种磁振子模式的符号相反。这一特征明确证实了MnF2中的交错磁性。该结果表明，极化INS对磁振子谱的精细结构十分敏感，在表征交错磁体方面具备较大应用前景。

附：英文原文

Title: Altermagnetism revealed by polarized neutrons in MnF2

Author: Quentin Faure, Dalila Bounoua, Victor Balédent, Arsen Gukasov, V. Ovidiu Garlea, Afonso Ribeiro, Jeffrey G. Rau, Sylvain Petit, Paul McClarty

Issue&Volume: 2026-10-29

Abstract: Altermagnets are compensated magnets with symmetry-enforced spin split bands. Direct spectroscopic evidence for their existence has been reported in several materials. For example, inelastic neutron scattering (INS) has recently been used to witness a splitting of magnon bands in MnTe that is compatible with altermagnetism. Here, we present polarized INS results on MnF2 showing that it is altermagnetic. Our data reveal a splitting coming from the long-range dipolar coupling. Furthermore, using a domain-biased sample, the data reveal a nonzero chirality in the neutron scattering cross section that reverses the sign between the two magnon modes. It is this feature that clearly demonstrates altermagnetism in MnF2. This finding highlights the potential for polarized INS to characterize altermagnets through its sensitivity to fine structure in magnon spectra.

DOI: 10.1126/science.aec2602

Source: https://www.science.org/doi/10.1126/science.aec2602