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arXiv · 1912.07157

Tailoring Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures

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.

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Peng Chen, Yong Zhang, Qi Yao, Fugu Tian, Lun Li, Zhengkun Qi, Xiaoyang Liu, Liyang Liao, Cheng Song, Jingyuan Wang, Jing Xia, Gang Li, David M. Burn, Gerrit van der Laan, Thorsten Hesjedal, Shilei Zhang, Xufeng Kou. 2019-12-16. Tailoring Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures. https://doi.org/10.1021/acs.nanolett.9b04932

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