Design of a multiband graphene-based absorber for terahertz applications using different geometric shapes

Abstract

By integrating multiple graphene-based geometric shapes, a unique absorber is proposed in this research, which achieves absorption peaks at 10 resonant frequencies, with an average absorption rate of 97.23% at terahertz frequency. The proposed structure consists of circular, triangular, square, pentagonal, and hexagonal ring-shaped absorbers to achieve multiband absorption. The proposed absorber is polarization-insensitive and has a wide incidence angle tolerance. Furthermore, increasing the graphene chemical potential value increases absorption while also tuning the resonance frequency. Additionally, this proposed configuration provides ultrawideband response at first band, with an absorption bandwidth percentage of 88.52. Two graphene-based absorbers are designed: one with geometric shapes that are in contact with one another and the other with geometric shapes that are not in contact with one another. Several investigations are exhibited on these two models to find the perfect combination of absorbers. The unique feature of this research is its novel, to the best of our knowledge, design and modeling, which provide absorption peaks at 10 resonant frequencies and also tuning of resonant frequency. All of these characteristics and findings distinguish the proposed multiband graphene-based absorber, which is well suited for terahertz applications.