A multi-scale numerical approach to model two-dimensional layered materials*

Since the discovery of single-layer graphene crystal, more different types of two-dimensional layered materials are exfoliated or synthesized. The theoretical modeling would guide the further design and understanding with these materials. We develop a multi-scale numerical approach to model these layers and their heterostructures. The microscopic modeling is based on the density functional theory (DFT) calculations followed by Wannier transformation to derive localized orbitals. These allow us to capture the effects from coupling with adjacent layers and the deformation within each layer from crystal relaxations. The faithful representation of the wavefunction characters also enables the computation of Berry curvatures and responses to external electric and magnetic fields.