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arXiv · 1409.6797

Interaction-induced quantum anomalous Hall phase in (111) bilayer of LaCoO$_3$

Yilin Wang·Zhijun Wang·Zhong Fang·Xi Dai
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Abstract

In the present paper, the Gutzwiller density functional theory (LDA+G) has been applied to study a bilayer system of LaCoO$_3$ grown along the $(111)$ direction on SrTiO$_3$. The LDA calculations show that there are two nearly flat bands located at the top and bottom of $e_{g}$ bands of Co atoms with the Fermi level crossing the lower one, which is almost half-filled. After including both the spin-orbit coupling and the Coulomb interaction in the LDA+G method, we find that the interplay between spin-orbit coupling and Coulomb interaction stabilizes a very robust ferromagnetic insulator phase with non-zero Chern number, which indicates the possibility to realize quantum anomalous Hall effect in this system.

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Yilin Wang, Zhijun Wang, Zhong Fang, Xi Dai. 2015-03-27. Interaction-induced quantum anomalous Hall phase in (111) bilayer of LaCoO$_3$. https://doi.org/10.1103/physrevb.91.125139

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