In response to the problems such as complex structure, poor tunability and limited working bandwidth existing in current terahertz broadband absorbers, this study designs a tunable terahertz absorber based on the proportionally arranged graphene. This device adopts a simple three-layer structure. By optimizing the size ratio of each resonant region of the surface graphene, it achieves a broadband and highly efficient absorption of over 90% in the frequency range of 2.69-5.92 THz, with an average absorption rate of 97.3%. It also has good impedance matching characteristics and angle adaptability. The research shows that the broadband absorption property of this device stems from the electric field coupling effect between different resonant units. This coupling effect enables multiple absorption peaks to overlap and broaden the bandwidth. Moreover, by applying an external voltage to regulate the Fermi level of graphene, the absorption bandwidth can be continuously adjusted. The device demonstrates flexible dynamic control capabilities and has good tolerance to the incident angle of electromagnetic waves. This study provides a feasible solution for designing a simple-structured and tunable high-efficiency terahertz absorber. This design has potential application value in the fields of terahertz detection, communication, and stealth technology.
Huang et al. (2026) studied this question.