Intrinsic anomalous Hall effect and Lifshitz transition in a ferromagnetic kagome-lattice metal

Abstract

Magnetic topological materials with broken time-reversal symmetry have demonstrated colossal intrinsic anomalous Hall effects, originating from large Berry curvature in momentum space. Here, we report the electrical transport study of a ferromagnetic kagome-lattice material Nd3Al, which is predicted to be a magnetic topological high symmetry line metal candidate. We observed a polarity reversal of ordinary Hall resistivity across 40 K, plainly indicating a perceptible shift in chemical potential and change of the Fermi surface, i.e., temperature-induced Lifshitz transition. More strikingly, as the shifting of Fermi level around the band (anti-)crossing points contributes to a considerable Berry curvature, the anomalous Hall conductivity ultimately stabilizes to a constant of approximately ∼427 Ω−1 cm−1 below 40 K, accompanied by a maximum anomalous Hall angle reaching 1.4%, conforming to the intrinsic dissipationless topological Berry-phase mechanism. The similar scaling behavior of anomalous Hall conductivity in Nd3Al to that of magnetic Weyl semimetal Co3Sn2S2 further signals the possible presence of nontrivial topological bands in kagome Nd3Al. In view of the kagome-lattice structure and predicted topological nature, our work unveils the significant potential of the large intrinsic anomalous Hall effect in Nd3Al for investing the interaction between ferromagnetism and topology.