Evolution of anomalous Hall effect in ferromagnetic Weyl semimetal Nb_xZr_1–xCo₂Sn

Magnetic topological semimetal can host various topological non-trivial states leading to exotic novel transport properties. Here we report the systematic magneto-transport studies on the Heusler alloy Nb_xZr_1−xCo₂Sn considered as a ferromagnetic (FM) Weyl semimetal. The cusp anomaly of temperature-dependent resistivity and large isotropic negative magneto-resistivity (MR) emerge around the FM transition consistent with the theoretical half-metallic predictions. The prominent anomalous Hall effect (AHE) has the same behavior with the applied field along various crystal directions. The Nb doping introduces more disorder resulting in the enhancement of the upturn for the temperature-dependent resistivity in low temperatures. With Nb doping, the AHE exhibits systemic evolution with the Fermi level lifted. At the doping level of x = 0.25, the AHE mainly originates from the intrinsic contribution related to non-trivial topological Weyl states.