(Anti)altermagnets: from spintronics to Ising superconductivity

In this talk, we provide an overview of the recently developed spin group theory of unconventional magnetic orders [1]. We focus on classes of even-partial-wave altermagnets (d-, g-, and i-wave) and odd-partial-wave anti-altermagnets (p-, f-, and h-wave), together with their spectroscopic signatures [1,2].

We further show how altermagnets and anti-altermagnets can enable robust or previously inaccessible functionalities in spintronics, multiferroic systems, and superconducting states. These include nonlinear current-induced spin polarization [3], the altermagnetoelectric effect [4,5], and potentially robust realizations of Ising superconductivity [6]. These results illustrate how unconventional magnetic order can provide alternative routes for controlling electronic and superconducting properties in quantum materials.

[1] Šmejkal, L., Sinova, J., and Jungwirth, T. Physical Review X 12, 031042 (2022).
[2] Jungwirth, T., Sinova, J., Fernandes, R. M., Liu, Q., Watanabe H., Murakami, S., Nakatsuji S., and Šmejkal, L. Nature 649, 837 (2026).
[3] Golub, L. E., Campos, W. H., and Šmejkal, L. arXiv:2503.12203 (2025).
[4] Šmejkal, L. arXiv:2411.19928 (2024).
[5] Fratian, G., Ramesh, M., et al. arXiv:2601.09970 (2026).
[6] Khodas, M., Šmejkal, L., and Mazin, I. I. arXiv:2601.19829 (2026).