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arXiv · 2112.06805

Spontaneous anomalous Hall effect arising from an unconventional compensated magnetic phase in a semiconductor

R. D. Gonzalez Betancourt·J. Zubáč·R. J. Gonzalez-Hernandez·K. Geishendorf·Z. Šobáň·G. Springholz·K. Olejník·L. Šmejkal·J. Sinova·T. Jungwirth·S. T. B. Goennenwein·A. Thomas·H. Reichlová·J. Železný·D. Kriegner
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Abstract

The anomalous Hall effect, commonly observed in metallic magnets, has been established to originate from the time-reversal symmetry breaking by an internal macroscopic magnetization in ferromagnets or by a non-collinear magnetic order. Here we observe a spontaneous anomalous Hall signal in the absence of an external magnetic field in an epitaxial film of MnTe, which is a semiconductor with a collinear antiparallel magnetic ordering of Mn moments and a vanishing net magnetization. The anomalous Hall effect arises from an unconventional phase with strong time-reversal symmetry breaking and alternating spin polarization in real-space crystal structure and momentum-space electronic structure. The anisotropic crystal environment of magnetic Mn atoms due to the non-magnetic Te atoms is essential for establishing the unconventional phase and generating the anomalous Hall effect.

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R. D. Gonzalez Betancourt, J. Zubáč, R. J. Gonzalez-Hernandez, K. Geishendorf, Z. Šobáň, G. Springholz, K. Olejník, L. Šmejkal, J. Sinova, T. Jungwirth, S. T. B. Goennenwein, A. Thomas, H. Reichlová, J. Železný, D. Kriegner. 2021-12-13. Spontaneous anomalous Hall effect arising from an unconventional compensated magnetic phase in a semiconductor. https://doi.org/10.1103/physrevlett.130.036702

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