▎ 摘　　要

We propose an all-graphene-dielectric tunable terahertz absorber composed of a graphene microstructure layer, a dielectric spacer layer and a metallic ground plane. The absorption performance and internal mechanism of the absorber have been comprehensively analyzed. When E-f changes from 0 eV to 0.6 eV, the absorption peak changes from 0.48 THz to 1.579 THz. In addition, we present a novel equivalent circuit model to analyze the mechanism of the absorber. The numerical calculation results are basically consistent with the result of the equivalent circuit model. Our work provides a reference for the design and theoretical study of all-graphene terahertz devices.