A new insight into defective one-dimensional dielectric-graphene photonic crystals

Abstract

Abstract The transmission properties of a defective one-dimensional dielectric-graphene stack are investigated by employing the transfer matrix method in the THz frequency range. The structure containing silicon dioxide as a defect layer consists of polyethylene and graphene nano-layers arranged in the pattern of (AG) N D(GA) M . The effect of the iteration numbers on the defect mode properties is studied to optimize the transmission peak. Analyzing structure with optimal iteration numbers indicates that the full width of half maximum is highly decreased. Subsequently, the quality factor is substantially enhanced as the thickness of the defect layer increases. It is also discussed how several parameters such as the incident angle, the state of polarization, and the permittivity of the layers affect the defect mode’s behavior. Our findings show that only in the case of ϵ A < 3 one can obtain the localized defect mode at frequencies between 1 and 2 THz. We also study the transmission characteristics with a focus on the variation of permittivity of the constituent layers. By increasing the incident angle, the peak intensity for the TM-polarized wave grows slightly, while it decreases for the TE-polarized wave. However, these changes are more striking in the case of ϵ A = 1 as compared to those in the case of ϵ A = 2.25. Photonic devices utilizing such defective structures may find application in filters and sensors operating in the THz range.