Defect‐Pattern‐Induced Fingerprints in the Electron Density of States of Strained Graphene Layers: Diffraction and Simulation Methods

The paper combines two theoretical approaches – the method of grazing dynamical diffraction (which allows performing the nondestructive structural diagnostics of defects in the near‐surface layers) with efficient numerical simulation method (which enables computation of electron structure in realistically large systems with millions of atoms) – for studying electronic properties in uniaxially strained graphene layers with point defects: impurity atoms. Electron density of states (DOS) is proved sensitive to the direction of uniaxial tensile deformation and configuration of defects. If defects are distributed orderly, the band gap value (estimated from the DOS curves) varies nonmonotonically versus the stretching deformation along zigzag‐edge direction. In this case, the minimal tensile strain required for the band gap opening is found to be smaller than that for defect‐free graphene, and the maximum band gap value is close to that predicted for failure limit of the defect‐free graphene. The obtained results play a significant part for band gap engineering in graphene: via spatial configuring of defects and external tensile stresses. The method of grazing dynamical diffraction and numerical simulations are combined in the process of studying the electronic properties of uniaxially strained graphene layers with point defects. The electron density of states is found to be sensitive to the direction of uniaxial tensile deformation and defect pattern. The nonmonotonic strain‐dependent band‐gap value in the electronic spectrum of graphene with ordered impurities is observed.