Above-room-temperature ferromagnetic state in a proximitized topological Dirac semimetal

We report an above-room-temperature ferromagnetic state realized in a proximitized Dirac semimetal, which is fabricated by growing typical Dirac semimetal Cd₃As₂ films on a ferromagnetic garnet with strong perpendicular magnetization. Observed anomalous Hall conductivity with substantially large Hall angles is found to be almost proportional to the separation of the Weyl nodes and opposite in sign to magnetization, in agreement with a minimal model behavior. Theoretical calculations based on first-principles electronic structure of Cd₃As₂ also demonstrate that the Fermi-level dependent anomalous Hall conductivity reflects the Berry curvature originating in the split Weyl nodes. The present high-mobility Dirac-semimetal/ferromagnetic-insulator heterostructure will provide a novel platform for exploring Weyl-node transport phenomena and spintronic functions lately proposed for topological semimetals.