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Quantum Anomalous Hall Effect in Graphene-based Heterostructure.

ABSTRACT: Quantum anomalous Hall (QAH) effect, with potential applications in low-power-consumption electronics, is predicted in the heterostructure of graphene on the (001) surface of a real antiferromagnetic insulator RbMnCl3, based on density-functional theory and Wannier function methods. Due to the interactions from the substrate, a much large exchange field (about 280 meV) and an enhanced Rashba spin-orbit coupling are induced in graphene, leading to a topologically nontrivial QAH gap opened in the system. The avenues of enhancing the nontrivial gap are also proposed, from which nearly a gap one order large is achieved. Our work demonstrates that this graphene-based heterostructure is an appropriate candidate to be employed to experimentally observe the QAH effect and explore the promising applications.

SUBMITTER: Zhang J

PROVIDER: S-EPMC4448525 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Quantum Anomalous Hall Effect in Graphene-based Heterostructure.

Zhang Jiayong J Zhao Bao B Yao Yugui Y Yang Zhongqin Z

Scientific reports 20150529

Quantum anomalous Hall (QAH) effect, with potential applications in low-power-consumption electronics, is predicted in the heterostructure of graphene on the (001) surface of a real antiferromagnetic insulator RbMnCl3, based on density-functional theory and Wannier function methods. Due to the interactions from the substrate, a much large exchange field (about 280 meV) and an enhanced Rashba spin-orbit coupling are induced in graphene, leading to a topologically nontrivial QAH gap opened in the ...[more]

PMID: 26024508

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