The electronic structure and spin states of 2D graphene/VX₂ (X = S, Se) heterostructures

Abstract

The structural, magnetic and electronic properties of 2D VX₂ (X = S, Se) monolayers and graphene/VX₂ heterostructures were studied using a DFT+U approach. It was found that the stability of the 1T phases of VX₂ monolayers is linked to strong electron correlation effects. The study of vertical junctions comprising of graphene and VX₂ monolayers demonstrated that interlayer interactions lead to the formation of strong spin polarization of both graphene and VX₂ fragments while preserving the linear dispersion of graphene-originated bands. It was found that the insertion of Mo atoms between the layers leads to n-doping of graphene with a selective transformation of graphene bands keeping the spin-down Dirac cone intact.