Large unsaturated transverse and negative longitudinal magnetoresistance in the compensated semimetal MoGe2

We report the experimental results of magnetotransport on the single crystal MoGe2, which was theoretically predicated to be a topological insulator. The resistivity of MoGe2 exhibits a metallic behavior at zero field, while with magnetic fields applied along the z axis and perpendicular to current, MoGe2 presents an upturn resistivity behavior and unsaturated quadratic large magnetoresistance (MR). The analysis of Hall effect shows that MoGe2 is a compensated semimetal with high mobilities at low temperatures, which is the origin of resistivity upturn and unsaturated large MR. As magnetic fields parallel to current, MoGe2 shows a weak antilocalization effect at low fields and a pronounced negative MR at higher fields, which is analogous to the picture of the Adler-Bell-Jackiw axial anomaly. Our results indicate that MoGe2 is a topological semimetal rather than a topological insulator, and will encourage further theoretical and experimental investigations on this compound.

Automated summary

Our experimental results on MoGe2 show metallic behavior with special resistivity effects under magnetic fields, indicating that the material is a topological semimetal rather than a topological insulator.