Single crystals of α-MnTe were synthesized by chemical vapor transport using iodine as the transport reagent. Structural characterization by powder x-ray diffraction confirmed the hexagonal structure (space group P63/mmc). Magnetization M(T) and specific heat Cp(T) measurements revealed an antiferromagnetic phase transition at TN≈307 K. The magnetic entropy derived from the Cp(T) data is consistent with the S=5/2 spin state of Mn2+ ions. Angle- and field-dependent magnetization measurements indicate complex magnetic responses associated with domains, and show an anomaly around 1 T. These features are analyzed using a phenomenological micromagnetic model that includes higher-order anisotropic exchange interactions coupling the weak ferromagnetic component and the antiferromagnetic order parameter. The model captures the generic behavior of magnetic states and demonstrates that the observed uniaxial and unidirectional anisotropies arise from metastable domain configurations and irreversible magnetization processes.
@article{arxiv.2511.01388,
title = {Low-field magnetization processes of hexagonal easy-plane altermagnet $\alpha$-MnTe},
author = {Sahana Rößler and Victoria Ginga and Marcus Schmidt and Yurii Prots and Helge Rosner and Ulrich Burkhardt and Ulrich K. Rößler and Alexander A. Tsirlin},
journal= {arXiv preprint arXiv:2511.01388},
year = {2025}
}