Stacking-tuned quantum anomalous Hall effect and multi-phase transition in Kagome lattice V2Se3†

The physical properties induced by layer stacking in two dimensional materials are fascinating. Here, a hexagonal Kagome lattice V₂Se₃ is constructed to investigate the dependence of the quantum anomalous Hall effect (QAHE) and the phase transition on the different stacking. Based on first principles calculations, the tight-binding model, and the irreducible representations, it is found that QAHE with a Chern number of 1 can be realized in the V₂Se₃ monolayer. While the V₂Se₃ bilayer is constructed, the interlayer interaction affects the Dirac cone, so QAHE with Chern number changes from −1 to 2 can be obtained by changing the different stacking patterns. On the other hand, applying biaxial tensile strain and changing stacking patterns in the V₂Se₃ bilayer will affect the d orbitals of the V atoms. In bilayer V₂Se₃, applying biaxial tensile strain affects the d orbitals of the V atoms that constitute the Dirac cone, and then a topological phase transition appears. Moreover, changing the stacking patterns induces the hybridization competition of the d orbitals, which leads to a magnetic phase transition. Constructing a Kagome bilayer and changing their stacking patterns paves a pathway in exploring quantum effects of topology and magnetism in layered materials.