Electronic structure of bilayer graphene with defects under an external electric field

Abstract

The electronic structure of bilayer graphene, where one of its layers possesses divacancies (DVs) or Stone-Wales (SW) defects, under an external electric field is studied within the framework of the density functional theory. Our calculations show that the Fermi level of bilayer graphene with DVs strongly depends on gate voltage, while that of bilayer graphene with SW defects is insensitive to gate voltage, indicating that the Fermi level tuning of graphene thin films with defects depends on the defect species and relative arrangement to the gate electrode. The electronic energy band of bilayer graphene under an external electric field is asymmetrically modulated with respect to the gate arrangements.