▎ 摘　　要

To construct photodetector and photovoltaic devices, light absorption is crucial. Herein, the absorption properties of a photonic crystal (PhC) consisting of high- and low-index dielectric materials and a metamaterial defect layer are investigated. Two graphene sheets are assumed to surround the metamaterial layer. The study is theoretically investigated and numerically simulated in the gigahertz region. The metamaterial negative permittivity and permeability are assumed to follow the Drude model. The number of unit cells, graphene chemical potential (GCP), graphene phenomenological scattering rate (GPSR), and the metamaterial layer thickness are varied to examine the PhC tunable absorption properties. The following points are demonstrated: 1) the number of absorbance peaks increases as the number of unit cells increases; 2) when the GCP increases, the absorbance peaks dramatically decay; 3) the number of absorbance peaks in the absorption spectrum is independent of the GCP and GPSR; and 4) the absorbance peaks exhibit a significant enhancement with increasing GPSR. The proposed PhC can be used to design optical devices based on graphene and metamaterials, such as sensors, filters, and absorbers in the GHz range.