Terahertz Selective Active Electromagnetic Absorption Film Based on Single-layer Graphene

In this paper, a terahertz selective active electromagnetic frequency absorption film based on single-layer graphene is proposed. The film can achieve electromagnetic wave absorption rate higher than 0.9 at 2.4-4 THz and 7-8.6 THz in the THz band. And, through parameter inversion analysis of the relative impedance, it is found that the relative impedance of the film in the strong absorption part matches the free space impedance, which is consistent with the classical theory. The absorption mechanism of the high absorption of the film is also studied by analyzing the electric field distribution and the pattern changed simulation of graphene. The film has good stability at different incident angles and shows strong polarization incoherence. The characteristics of the film can be tuned by tuning the physical parameters, graphene Fermi energy and relaxation time. Interestingly, under some parameters, the film will change the original absorption mode. This paper introduces five absorption modes: double bandwidth absorption mode, two different single bandwidth absorption mode and two different double peak and bandwidth absorption mode. To sum up, the film has strong application value in aerospace, military, medical and other fields.