In this paper, we investigate the absorption characteristic of the graphene-stack-based metamaterial absorber at the lower terahertz frequency range for the ultrathin and ultrabroadband. The absorption spectrum can be dynamically controlled by changing the gate voltage on the graphene-stack cavity. The thickness of a designed structure is only λ₀/25.5 with respect to the center frequency. The absorption principle is discussed by modeling equivalent circuit and studying the distribution of electric field and surface currents. The simulated results show that the high absorption above 0.9 in the frequency range of 1.24 THz~2.08 THz can be obtained. The absorption performance is insensitive to different incidence angles. The research results have great application potentials in the design of the terahertz device.

在本文中，我们研究了超薄和超宽带在较低太赫兹频率范围内基于石墨烯堆栈的超材料吸收剂的吸收特性。吸收光谱可以通过改变石墨烯堆叠腔上的栅极电压来动态控制。所设计的结构的厚度是仅λ ₀相对于中心频率为/25.5。通过对等效电路建模并研究电场和表面电流的分布，讨论了吸收原理。仿真结果表明，在1.24 THz〜2.08 THz的频率范围内，可以获得0.9以上的高吸收。吸收性能对不同的入射角不敏感。研究结果在太赫兹器件的设计中具有很大的应用潜力。