Dielectric Constant and van der Waals Interlayer Interaction of MoS2-Graphene Heterostructures

The dielectric screening is one of the most fundamental properties of 2D materials which is used to characterize electronic properties such as storage capacity of charge or energy. We numerically investigate three potential heterostructures of MoS2-Graphene and their corresponding interlayer interactions. Applying a density-functional approach to the lowest energy structure of the interlayer, we find that, within a lower field regime (≲ 10 MV/cm), the dielectric constant is independent of the vertical electric field and dependent of the interlayer distance and stacking pattern of heterostructures composed of MoS2 and Graphene. From the calculation results of the induced charge throughout the heterostructure, we find how the van der Waals interaction influences the dielectric constant.