Temperature-induced anomalous magnetotransport in the Weyl semimetal Mn3Ge

The magnetic Weyl semimetallic state can lead to intriguing magnetotransport, such as chiral anomaly and the layered quantum Hall effect. Mn3X (X = Sn, Ge) is a noncollinear antiferromagnetic semimetal where a Weyl semimetallic state is stabilized by time-reversal symmetry breaking. Compared to the well-studied Mn3Sn, the Weyl fermion-induced magnetotransport in Mn3Ge has been merely studied. Here, we report an in-depth study on the magnetotransport in a microfabricated Mn3Ge single crystal from room temperature to 10 K. We reveal an anomalous anisotropic magnetoresistance with fourfold symmetry and a positive high-field longitudinal magnetoresistance below the critical temperature (160-170 K). The possible origin is the temperature-induced tilting of the Weyl nodes. Our study helps to understand the magnetotransport properties in the Weyl fermion system.

Automated summary

In this study, the magnetotransport properties of a microfabricated Mn3Ge single crystal were investigated. Anomalous anisotropic magnetoresistance with fourfold symmetry and positive high-field longitudinal magnetoresistance below the critical temperature were observed. The temperature-induced tilting of the Weyl nodes may be the possible cause. This study contributes to the understanding of magnetotransport properties in the Weyl fermion system.