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arXiv · 1907.03711

Quantum Anomalous Hall Effect by Coupling Heavy Atomic Layers with CrI$_{3}$

Majeed Ur Rehman·Xinlong Dong·Tao Hou·Zeyu Li·Shifei Qi·Zhenhua Qiao
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Abstract

We explored the possibility of realizing quantum anomalous Hall effect by placing heavy-element atomic layer on top of monolayer CrI$_{3}$ with a natural cleavage surface and broken time-reversal symmetry. We showed that CrI$_{3}$/X (X = Bi, Sb, or As) systems can open up a sizable bulk gap to harbour quantum anomalous Hall effect, e.g., CrI$_{3}$/Bi is a natural magnetic insulator with a bulk gap of 30~meV, which can be further enlarged via strain engineering or adjusting spin orientations. We also found that the ferromagnetic properties (magnetic anisotropic energy and Curie temperature) of pristine CrI$_{3}$ can be further improved due to the presence of heavy atomic layers, and the spin orientation can be utilized as a useful knob to tune the band structure and Fermi level of CrI$_{3}$/Bi system. The topological nature, together with the enhanced ferromagnetism, can unlock new potential applications for CrI$_{3}$-based materials in spintronics and electronics.

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Majeed Ur Rehman, Xinlong Dong, Tao Hou, Zeyu Li, Shifei Qi, Zhenhua Qiao. 2019-07-08. Quantum Anomalous Hall Effect by Coupling Heavy Atomic Layers with CrI$_{3}$. https://doi.org/10.1103/physrevb.100.195422

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