Spontaneous anomalous Hall effect arising from antiparallel magnetic order in a semiconductor

Dominik KRIEGNER

Recently, a distinct mechanism of anomalous Hall effect, the so-called crystal Hall effect, was predicted to arise from antiparallel magnetic moments surrounded by cages of nonmagnetic atoms [1]. In my talk I will report on the observation of this spontaneous anomalous Hall effect in thin films of semiconducting MnTe with well-established room-temperature collinear antiparallel magnetic ordering [2]. In MnTe, tellurium octahedra surround the magnetic manganese atoms and break sufficient symmetries to enable k-dependent spin splitting in the band structure and associated effects like the anomalous Hall effect. The observed spontaneous Hall signal, i.e. present at zero magnetic field, is consistent with the experimental magnetic easy axis and vanishes with the magnetic order. Our experimental results are compared with first principle calculations of the crystal Hall conductivity.

[1] L. Šmejkal, A. H. MacDonald, J. Sinova, S. Nakatsuji, and T. Jungwirth, Anomalous Hall antiferromagnets, Nature Reviews Materials , 1 (2022)
[2] R. D. Gonzalez Betancourt, J. Zubáč, R. J. Gonzalez-Hernandez, K. Geishendorf, Z. Šobáň, G. Springholz, K. Výborný, K. Olejník, L. Šmejkal, J. Sinova, T. Jungwirth, S. T. B. Goennenwein, A. Thomas, H. Reichlová, J. Železný, D. Kriegner, submitted arXiv:2112.06805