Direct Imaging of Antiferromagnet-Ferromagnet Phase Transition in van der Waals Antiferromagnet CrSBr

Authors：Yu, Jingjing; Liu, Daxiang; Ding, Zhenyu; Yuan, Yanan; Zhou, Jiayuan; Pei, Fangfang; Pan, Haolin; Ma, Tianping; Jin, Feng; Wang, Lingfei; Zhu, Wenguang; Wang, Shouguo; Wu, Yizheng; Liu, Xue; Hou, Dazhi; Gao, Yang; Qiu, Ziqiang^*; Yang, Mengmeng^*; Li, Qian^*

Source：Advanced Functional Materials, 2023.

DOI：10.1002/adfm.202307259

• antiferromagnet-ferromagnet phase transitions
• direct imaging of AFM Neel vector orientation
• magneto-optic anisotropy
• spin-flop state
• van der Waals antiferromagnets

The advent of van der Waals (vdW) ferromagnetic (FM) and antiferromagnetic (AFM) materials offers unprecedented opportunities for spintronics and magneto-optic devices. Combining magnetic Kerr microscopy and density functional theory calculations, the AFM-FM transition is investigated and a surprising abnormal magneto-optic anisotropy in vdW CrSBr associated with different magnetic phases (FM, AFM, or paramagnetic state) is discovered. This unique magneto-optic property leads to different anisotropic optical reflectivity from different magnetic states, permitting direct imaging of the AFM Neel vector orientation and the dynamic process of the AFM-FM transition within a magnetic field. Using Kerr microscopy, not only the domain nucleation and propagation process is imaged but also the intermediate spin-flop state in the AFM-FM transition is identified. The unique magneto-optic property and clear identification of the dynamics process of the AFM-FM phase transition in CrSBr demonstrate the promise of vdW magnetic materials for future spintronic technology. @@@ Combining magnetic Kerr microscopy and density functional theory calculations, a successful imaging of antiferromagnetic-ferromagnetic (AFM-FM) phase transition in van der Waals (vdW) AFM CrSBr based on its unique magneto-optic property is demonstrated. These findings reveal enormous prospects for magnetism imaging and control in 2D spintronics with vdW AFM.image

• Institution
  中国科学院; 复旦大学