Large anomalous Hall effect in α-MnTe thin films grown on
Phys. Rev. B 114, 194403 – Published 6 October, 2026
DOI: https://doi.org/10.1103/4hdt-17r9
Abstract
α-MnTe is a prototypical altermagnet exhibiting a strong anomalous Hall effect (AHE), despite having a nearly vanishing magnetization. has a small lattice mismatch with MnTe and a matching coefficient of thermal expansion; there are, however, no reports on measurements of the AHE in α-MnTe epitaxially grown on this substrate. Here, we report the measurement of an AHE and x-ray magnetic circular dichroism in α-MnTe films grown on that have a relaxed crystal structure and nearly vanishing magnetization confirmed experimentally. We study films of varying thickness, all of which exhibit a consistent spontaneous anomalous Hall effect, albeit only at low temperature. With increasing thickness, we find that films become more resistive and that their anomalous Hall conductivity decreases as their longitudinal conductivity decreases. Importantly, a comparison of the anomalous Hall conductivity per unit magnetization with other magnetic semiconductors reveals the colossal amplitude of the AHE of α-MnTe. We carry out this analysis for the films reported here and for previous results from the literature. Such a colossal AHE cannot be explained by a picture where defects induce extrinsic ferromagnetism in this material, and must be a result of the magnetocrystalline symmetry allowing its altermagnetism.
