Large anomalous Hall and Nernst effects dominated by an intrinsic mechanism in the noncollinear ferromagnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>PrMn</mml:mi> <mml:mn>2</mml:mn> </mml:msub> <mml:msub> <mml:mi>Ge</mml:mi> <mml:mn>2</mml:mn> </mml:msub> </mml:mrow> </mml:math>
Meng Lyu, Junyan Liu, Shen Zhang, Yang Liu, Jinying Yang, Yibo Wang, Yiting Feng, Binbin Wang, Hongxiang Wei, Enke Liu
Abstract
The anomalous transverse transport properties, including the anomalous Hall and Nernst effects, are crucial for probing the topological band features in magnetic materials. In this study, we present a comprehensive investigation of the magnetic, electrical, and thermal transport, as well as the electronic band structure, of the noncollinear ferromagnet ${\mathrm{PrMn}}_{2}{\mathrm{Ge}}_{2}$. Our findings reveal that ${\mathrm{PrMn}}_{2}{\mathrm{Ge}}_{2}$ exhibits prominent anomalous Hall and Nernst effects. Scaling analysis suggests that the anomalous Hall effect is predominantly influenced by the intrinsic Berry curvature contribution. Additionally, the large anomalous Nernst signal exceeds the magnetization scaling relations observed in conventional ferromagnets, and the calculated anomalous Nernst conductivity exhibits a $T\text{ln}T$ relation. These observations align with the behavior seen in other magnetic topological materials, further suggesting a substantial intrinsic Berry curvature effect. Complemented by detailed theoretical calculations, we clarify the electronic band properties and confirm a substantial net Berry curvature near the Fermi level in this compound. Our work elucidates that the large anomalous Hall and Nernst effects of ${\mathrm{PrMn}}_{2}{\mathrm{Ge}}_{2}$ are dominated by an intrinsic mechanism and presents it as a probable magnetic topological material with a significant Berry phase effect in the momentum space.