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Magnetizing topological surface states of Bi₂Se₃ with a CrI₃ monolayer.

ABSTRACT: To magnetize surfaces of topological insulators without damaging their topological feature is a crucial step for the realization of the quantum anomalous Hall effect (QAHE) and remains as a challenging task. Through density functional calculations, we found that adsorption of a semiconducting two-dimensional van der Waals (2D-vdW) ferromagnetic CrI₃ monolayer can create a sizable spin splitting at the Dirac point of the topological surface states of Bi₂Se₃ films. Furthermore, general rules that connect different quantum and topological parameters are established through model analyses. This work provides a useful guideline for the realization of QAHE at high temperatures in heterostructures of 2D-vdW magnetic monolayers and topological insulators.

SUBMITTER: Hou Y

PROVIDER: S-EPMC6544448 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Magnetizing topological surface states of Bi2Se3 with a CrI3 monolayer.

Hou Yusheng Y Kim Jeongwoo J Wu Ruqian R

Science advances 20190531 5

To magnetize surfaces of topological insulators without damaging their topological feature is a crucial step for the realization of the quantum anomalous Hall effect (QAHE) and remains as a challenging task. Through density functional calculations, we found that adsorption of a semiconducting two-dimensional van der Waals (2D-vdW) ferromagnetic CrI3 monolayer can create a sizable spin splitting at the Dirac point of the topological surface states of Bi2Se3 films. ...[more]

PMID: 31172028

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