理想阿尔特磁体是一类具有非相对论性自旋分裂带的列线性、晶体对称性强制完全补偿磁体，在这种系统中， Berry 曲率对磁光效应（MOEs）的贡献被有效时间反演对称性严格禁止。本文表明，在此类系统中，MOEs 仅由量子度量诱导，并且在现实中的阿尔特磁体中通常由它主导。我们将 Berry 曲率诱导的 MOEs 称为传统 MOEs，将量子度量主导的 MOEs 称为非常规 MOEs。我们推导出包含 Berry 曲率和量子度量的通用公式，用于阿尔特磁体中非常规 MOEs 的计算，从而能够定量评估它们各自的贡献。通过对称性分析，我们证明理想阿尔特磁体仅能表现出非常规 MOEs。利用三维规范阿尔特磁体 MnTe 和新兴的二维双层扭曲阿尔特磁体 CrSBr 作为示例，我们展示了非常规 MOEs 在阿尔特磁体中的普遍性。我们的结果确立了阿尔特磁体作为量子度量驱动光学现象的自然平台，大大扩展了 MOEs 的范围，并提供了可以在未来实验研究中验证的具体预测。
英文摘要：
The ideal altermagnets are a class of collinear, crystal-symmetry-enforced fully compensated magnets with nonrelativistic spin-split bands, in which contributions from Berry curvature to magneto-optical effects (MOEs) are strictly forbidden by an effective time-reversal symmetry. Here we show that, in such systems, MOEs are exclusively induced by the quantum metric and, in realistic altermagnets, are typically dominated by it. We refer to Berry-curvature-induced MOEs as conventional MOEs and to quantum-metric-dominated MOEs as unconventional MOEs. We derive general formulas that incorporate both Berry curvature and quantum metric for unconventional MOEs in altermagnets, enabling a quantitative evaluation of their respective contributions. Through symmetry analysis, we prove that ideal altermagnets are constrained to exhibit only unconventional MOEs. Using the three-dimensional canonical altermagnet MnTe and the emerging two-dimensional bilayer twisted altermagnet CrSBr as illustrative examples, we demonstrate that unconventional MOEs are prevalent in altermagnets. Our results establish altermagnets as a natural platform for quantum-metric-driven optical phenomena, substantially broadening the scope of MOEs and providing concrete predictions that can be tested in future experimental studies.
Symmetry-Driven Unconventional Magnetoelectric Coupling in Perovskite Altermagnets: From Bulk to the Two-Dimensional Limit
Eastern Institute of Technology（宁波东方理工大学）；Ningbo Institute of Digital Twin, Eastern Institute of Technology（宁波东方理工大学数字孪生研究院）；Eastern Institute for Advanced Study, Eastern Institute of Technology（宁波东方理工大学高等研究院）；School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院）；School of Physical Science and Technology, Suzhou University of Science and Technology（苏州科技大学物理科学与技术学院）
Building unconventional magnetic phases on graphene by H atom manipulation: From altermagnets to Lieb ferrimagnets
Universidad Autónoma de Madrid（马德里自治大学）；Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid（马德里自治大学凝聚态物理中心）；Instituto Nicolás Cabrera (INC), Universidad Autónoma de Madrid（马德里自治大学尼古拉斯·卡布雷拉研究所）
3D bulk-resolved $g$-wave altermagnetic order parameter in CrSb
Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪什实验室）；Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf（德累斯顿强磁场实验室（HLD-EMFL），德累斯顿-罗斯多夫亥姆霍兹中心）；National High Magnetic Field Laboratory（国家高磁场实验室）
研究 CrSb 中非常规磁体的序参量对称性，通过磁量子振荡测量，在 CrSb 布里渊区不同方向旋转磁场，利用其反铁磁带结构特性，精确映射序参量对称性，确立 CrSb 为典型 g 波金属反铁磁体。
Dirac points and Weyl phase in a honeycomb altermagnet
Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, State Key Laboratory of Optoelectronic Materials and Technologies, Center for Neutron Science and Technology, School of Physics, Sun Yat-Sen University（中山大学物理学院）
Intrinsic Spin Filter Effect in a $d$-wave altermagnet KV$_2$Se$_2$O with Open Fermi Surface
School of Science, Sun Yat-sen University（中山大学理学院）；Department of Physics and Astronomy, University of Florence（佛罗伦萨大学物理与天文学系）；Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University（武汉大学物理科学与技术学院人工微结构和量子调控教育部重点实验室）；The State Key Laboratory for Refractories and Metallurgy, Wuhan University of Science and Technology（武汉科技大学耐火材料与冶金国家重点实验室）；Laboratory for Computational Physical Sciences (MOE), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University（复旦大学物理系表面物理国家重点实验室计算物理科学教育部重点实验室）；Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, Sun Yat-sen University（中山大学广东省磁电物理与器件重点实验室）
All optical excitation of spin polarization in d-wave altermagnets
RPTU University Kaiserslautern-Landau（凯泽斯劳滕-兰道 RPTU 大学）；Johannes Gutenberg University Mainz（美因茨约翰内斯·古腾堡大学）；Universidade de Santiago de Compostela（圣地亚哥-德孔波斯特拉大学）；Tohoku University（东北大学）
Strain-Tunable Shift Current and Magneto-Optical Kerr Effect in Multiferroic Altermagnet Fe2Mo3O8
Jilin University（吉林大学）；Suzhou Laboratory（苏州实验室）；Institute of Materials Science, Technology University of Darmstadt（达姆施塔特工业大学材料科学研究所）；University of Salzburg（萨尔茨堡大学）；College of Physics, Jilin University（吉林大学物理学院）
Ultrafast Magneto-optical Fingerprints of Altermagnetism in MnTe
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所北京凝聚态物理国家研究中心）；Department of Physics, The Hong Kong University of Science and Technology（香港科技大学物理系）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；Songshan Lake Materials Laboratory（松山湖材料实验室）
Spin polarization engineering in $d$-wave altermagnets
Georgetown University（乔治城大学）；Max Planck Institute for the Physics of Complex Systems（马克斯·普朗克复杂系统物理研究所）；Uppsala University（乌普萨拉大学）；Center for Quantum Spintronics, Department of Physics, Norwegian University of Science and Technology（挪威科技大学物理系量子自旋电子学中心）；Max Planck Institute for Chemical Physics of Solids（马克斯·普朗克固体化学物理研究所）；Institute of Physics, Czech Academy of Sciences（捷克科学院物理研究所）
Band topology and symmetry-driven magneto-optical response in two-dimensional d-wave altermagnets with staggered spin-orbit coupling
International Research Centre Magtop, Institute of Physics, Polish Academy of Sciences（波兰科学院物理研究所）；Department of Physics, University of Guilan（吉兰大学物理系）；Institute of Theoretical Physics, Jagiellonian University（雅盖隆大学理论物理研究所）
Nonlinear Magnetoelectric Effect under Magnetic Octupole Order: Its Application to a $d$-Wave Altermagnet and a Pyrochlore Lattice with All-In/All-Out Magnetic Order
Karlsruhe Institute of Technology（卡尔斯鲁厄理工学院）；University of Illinois Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；ICTP South American Institute for Fundamental Research（国际理论物理中心南美基础研究所）
Unconventional Magnetism: Symmetry Classification, Hybrid-parity and Unconstrained-parity Classes
Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences（中国科学院合肥物质科学研究院）；School of Physical Science and Technology, Inner Mongolia University（内蒙古大学物理科学与技术学院）；Institute of Physical Science and Information Technology, Anhui University（安徽大学物理与材料科学学院）；Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences（中国科学院合肥物质科学研究院固体物理研究所）；Research Center for Quantum Physics and Technologies, Inner Mongolia University（内蒙古大学量子物理与技术研究中心）；Inner Mongolia Key Laboratory of Microscale Physics and Atomic Manufacturing, Inner Mongolia University（内蒙古微尺度物理与原子制造重点实验室）；Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology（北京理工大学物理学院）
