Magneto-optical effects, such as those which bear the name of John Kerr or Michael Faraday, have traditionally been associated with ferromagnets. About ten years ago, the solid state physics community embraced the idea of anomalous Hall effect (AHE) being present in antiferromagnets (AFM) too and soon, this view proliferated into the field of magneto-optics. In our talk, we will summarise the history of departure from "AHE proportional to magnetisation" paradigm starting with the work of Shindou and Nagaosa [1] discussing both collinear [2] and non-collinear [3] AFMs. By analogy, we will then introduce magneto-optical Kerr effect (MOKE) and discuss recent experimental results on collinear [4] and non-collinear systems alongside ferrimagnets [5,6].

[1] R. Shindou and N. Nagaosa, Phys. Rev. Lett. 87, 116801 (2001)
[2] K. Kluczyk et al., Phys. Rev. B 110, 155201 (2024)
[3] G. Gurung et al., Phys. Rev. Materials 3, 044409 (2019)
[4] M. Hubert et al., phys. stat. sol. (b) 2400541 (2025)
[5] F. Johnson et al., Phys. Rev. B 107, 014404 (2023).
[6] J. Zemen, J. Appl. Phys. 134, 203902 (2023).