Strain effects on the Schottky contacts of graphene and MoSe2 heterobilayers

Combining the electronic structures of two-dimensional monolayers in ultrathin heterostructures is expected to display new properties beyond their individual components. Here, first-principles calculations are performed to investigate the effect of strain on the electronic structures of graphene/MoSe2 heterostructures. We find that the intrinsic properties of both graphene and MoSe2 are preserved by the weak van der Waals (vdW) contact. Moreover, the n-type Schottky barrier to p-type Schottky barrier transition occurs when the heterostructure is subjected to the strain, which indicates that the Schottky barrier can be tuned effectively by the strain in the heterostructure. Notice that it is difficult to tune the Schottky contact to the Ohmic contact (no barrier) by using only the strain at the graphene/MoSe2 interface. Our studies provide a promising route to design new graphene-based heterostructures and explore its potential applications in nanoelectronic and optoelectronic devices.