First-principles study of optical properties of armchair graphene nanoribbons with divacancy defect

Abstract

Using first-principles calculations based on density functional theory, we systematically studied the electronic structures and optical properties of armchair graphene nanoribbons (AGNRs) with divacancy defects. We found that the structure of the nanoribbon was reorganized either as a parallel oriented divacancy or a sloping oriented one, and a defect state appeared in the band structure. In the low frequency region, the optical constants were anisotropic. Compared to the optical constant of the perfect AGNR, for the sloping- and parallel-oriented divacancy defects, the imaginary parts of the dielectric functions exhibited obvious red and blue shift, respectively.