Effects of strain and electric field on electronic structures and Schottky barrier in graphene and SnS hybrid heterostructures

The structural stability and electronic properties of monolayer and bilayer graphene with SnS hybrid heterostructures are studied by using the first-principle methods. The intrinsic electronic properties of SnS and graphene are preserved, and p-type Schottky contacts with the significantly small barrier height are formed in the van der Waals (vdW) heterostructures. In the graphene/SnS (G/S) heterostructure, the p-type Schottky contacts can be changed to Ohmic contacts by decreasing the interlayer distance, and it is also turned to n-type Schottky contacts by applying external electric field. However, the Schottky barrier of graphene/SnS/graphene (G/S/G) heterostructure is insensitive to the external electric field. Moreover, in the SnS/graphene/graphene (S/G/G) heterostructure, the external electric field can easily induce the transition from p-type to n-type Schottky contacts, then to Ohmic contacts. These studies provide a promising route to design new graphene-based vdW heterostructures and explore its potential applications in electronic and optoelectronic devices.