Tailoring the Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures.

Engineering the anomalous Hall effect (AHE) is the key to manipulate the magnetic orders in the emerging magnetic topological insulators (MTIs). In this letter, we synthesize the epitaxial BiTe/MnTe magnetic heterostructures and observe pronounced AHE signals from both layers combined together. The evolution of the resulting hybrid AHE intensity with the top BiTe layer thickness manifests the presence of an intrinsic ferromagnetic phase induced by the topological surface states at the heterolayer interface. More importantly, by doping the BiTe layer with Sb, we are able to manipulate the sign of the Berry phase-associated AHE component. Our results demonstrate the unparalleled advantages of MTI heterostructures over magnetically doped TI counterparts in which the tunability of the AHE response can be greatly enhanced. This in turn unveils a new avenue for MTI heterostructure-based multifunctional applications.