Tailoring Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures

TL;DR

This study demonstrates how engineering magnetic topological insulator heterostructures allows for tunable anomalous Hall effects, advancing potential applications in quantum computing and spintronics.

Contribution

We synthesized Bi2Te3/MnTe heterostructures and showed how their AHE can be tuned via layer thickness and doping, revealing new control mechanisms for magnetic topological insulators.

Findings

Pronounced AHE signals from heterostructures

Intrinsic ferromagnetic phase induced by surface states

AHE sign manipulation through Sb doping

Abstract

Engineering the anomalous Hall effect (AHE) in the emerging magnetic topological insulators (MTIs) has great potentials for quantum information processing and spintronics applications. In this letter, we synthesize the epitaxial Bi2Te3/MnTe magnetic heterostructures and observe pronounced AHE signals from both layers combined together. The evolution of the resulting hybrid AHE intensity with the top Bi2Te3 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 Bi2Te3 layer with Sb, we are able to manipulate the sign of the Berry phase-associated AHE component. Our results demonstrate the un-paralleled 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.