Epitaxial growth of Kagome semimetal Mn3Ge

Materials with layered Kagome lattice allow the interplay of topological properties and interactions in flat bands, and can give rise to spin liquids, skyrmions and other phases. Mn₃Ge as noncollinear antiferromagnet is Kagome semimetal, which hosts large anomaly in transverse charge transport and spin Hall angle. As an ideal material candidate for topological physics as well as antiferromagnetic spintronics, synthesis of high quality Mn₃Ge epitaxial thin film is highly in demand and has been of great interest among experimentalists. Here, high quality epitaxial Mn₃Ge films have been synthesized by two different techniques: magnetron co-sputtering [1] as well as molecular beam epitaxy. Both in-situ and ex-situ characterizations indicate these films are highly crystalline and c-axis oriented. Highly ordered atomic layers are captured by scanning transmission electron microscopy. Large anomalous Nernst effect as well as spin to charge conversion by FMR have been measured, which can be related to non-vanishing Berry curvature in reciprocal space. This work makes tunability in topological semimetal possible and opens a pathway for both the Kagome materials related physics and devices.