Magnetic and magneto-transport properties of non-collinear antiferromagnetic Mn3Ge epitaxial films

Antiferromagnetic Mn3X (X = Sn, Ge, Ga, and Pt) possessing non-collinear spin structures with Kagome lattices have attracted increasing interest because of their unique properties, such as significant anomalous Hall and magneto-optical Kerr effects. Recent advances in spintronic devices that use non-collinear antiferromagnets have inspired research into various materials for exploiting their potential. In this study, we investigated the magnetic and magneto-transport properties of 11̄00-oriented epitaxial and polycrystalline Mn3Ge films deposited by magnetron sputtering. Anomalous Hall conductivity monotonically decreases with temperature in an epitaxial Mn3Ge film, whereas the polycrystalline sample demonstrates a different trend. Furthermore, we obtained a large in-Kagome-plane uniaxial magnetic anisotropy of epitaxial Mn3Ge above ambient temperature, thereby leading to higher thermal stability and robustness against the external field. Our results indicate the potential of Mn3Ge for future functional, high-speed, and high-density spintronics devices using antiferromagnets.