Strain effect on electronic structure of La-doped monolayer graphene

As a basic block of carbon materials with different dimensions, graphene has shown great potential in novel device field. As a result, it becomes extremely important to break the zero-band-gap status of graphene sheet. In this work, the density functional theory (DFT) has been carried out to calculate the electronic structure of La-doped monolayer graphene under both X-direction uniaxial and Y-direction uniaxial strain. It turns out that both tensile uniaxial strain along the X-direction and compressive strain along the Y-direction help to broaden bandgap in La-doped graphene sheet. In addition, the La-doped graphene could get a biggest band gap while these two kinds of uniaxial strains are given to be 12% and −9%, respectively.