Altermagnetism in Thin Films: From Band Splitting to Functional Responses

Altermagnets are compensated collinear magnets in which opposite sublattices are connected by lattice rotations rather than translations [1]. This symmetry causes a spin‑split band structure whose sign alternates in momentum space while the net magnetization vanishes. We recently demonstrated such band splitting in hexagonal MnTe [2], where it also enables linear responses traditionally associated with ferromagnets [3-7]. In this talk I will discuss our progress in extending altermagnetism to sputtered thin films and thermoelectric phenomena [8,9]. These films provide a platform to explore spin‑split bands and their spin‑transport signatures. The results highlight altermagnetism as a promising platform for spintronics [10].

[1] L. Smejkal, J. Sinova, and T. Jungwirth, Phys. Rev. X 12, 031042 & 040501 (2022).

[2] J. Krempaský et al., Nature 626, 517–522 (2024).

[3] R. D. Gonzalez Betancourt et al., Phys. Rev. Lett. 130, 036702 (2023).

[4] R. D. Gonzalez Betancourt et al., npj Spintronics 2, 45 (2024).

[5] H. Reichlova et al., Nat. Commun. 15, 4961 (2024).

[6] A. Hariki et al., Phys. Rev. Lett. 132, 176701 (2024).

[7] O. J. Amin et al., Nature 636, 348–353 (2024).

[8] S. P. Bommanaboyena et al., Phys. Rev. Materials 9, 064402 (2025).

[9] A. Badura et al., Nat. Commun. 16, 7111 (2025).

[10] T. Jungwirth, J. Sinova, P. Wadley, D. Kriegner, H. Reichlova, F. Krizek, H. Ohno, L. Smejkal, arXiv:2508.09748 [cond-mat.mtrl-sci]