Robust quantum anomalous Hall effect with tunable magnetization directions and Chern numbers
Xinming Wu, Runhan Li, Xiaorong Zou, Baibiao Huang, Ying Dai, Chengwang Niu
Abstract
The quantum anomalous Hall effect (QAHE) has attracted significant attention as it provides intriguing platforms for exploring prominent physical phenomena and applications of low-dissipation devices. Here, we put forward that, unlike previously reported QAH insulators emerging with either out-of-plane or in-plane magnetizations, robust QAHE can be obtained in a two-dimensional ferromagnet regardless of the magnetization directions. In particular, we identify the intrinsic ferromagnetic ${\mathrm{NiBiO}}_{3}$ as a feasible candidate material with the nontrivial topology explicitly confirmed by nonzero integer Chern numbers $\mathcal{C}$ and the emergence of chiral edge states. Moreover, we proclaim that the Chern numbers can be tuned and a high-Chern-number QAHE, characterized by $\mathcal{C}=\ifmmode\pm\else\textpm\fi{}3$, is obtained by tuning the magnetization from the in-plane to out-of-plane direction. Our findings not only advance the general understanding of QAHE but also put forward potential applications in topotronics.