Tunable high Chern-number quantum anomalous Hall effect through interlayer ferromagnetic coupling in two-dimensional ferromagnet NiSbO3

TL;DR

This paper predicts that monolayer NiSbO3 exhibits a high Chern-number quantum anomalous Hall effect with C=3, which can be doubled to C=6 in bilayers due to interlayer ferromagnetic coupling, promising for quantum devices.

Contribution

It introduces monolayer NiSbO3 as a new material exhibiting high Chern-number QAHE and demonstrates how interlayer coupling enhances this effect.

Findings

Monolayer NiSbO3 has C=3 QAHE confirmed by edge states.

The Curie temperature of NiSbO3 is approximately 291 K.

Bilayer NiSbO3 achieves C=6 QAHE due to interlayer ferromagnetic coupling.

Abstract

The high Chern-number quantum anomalous Hall effect (QAHE) is significant and fascinating due to the presence of multiple dissipationless chiral edge states. Here, we predict that monolayer NiSbO3 possesses the Chern number C = 3, confirmed by the anomalous Hall conductance and the chiral edge states. The magnetic anisotropic energy (MAE) responsible for ferromagnetic order is 0.641 meV originating from Ni-d and Sb-p orbitals, where the contributed MAE from same spin-up channels predominates. In forward electric fields, the negative MAE makes the easy magnetization direction perpendicular to the surface, which is conducive to the realizing of high Chern-number QAHE. The simulated Curie temperature is 291 K. Intriguingly, in a bilayer, the obtained C = 6 is twice that of the monolayer, thanking to the interlayer ferromagnetic coupling. Our work offers a promising candidate for potential applications in topological quantum devices and spintronics.