RETRACTED: Ultra-wideband terahertz absorber based on graphene modulation

Abstract

Here we propose an ultra-wideband terahertz absorber (UWTA), which is composed of substrate, dielectric, and five-layer graphenes. By changing the chemical potential of graphene, the absorption coefficient of UWTA is larger than 0.9 from 1.51–8.25 THz. The absorption bandwidth is 6.74 THz. The relative bandwidth is 138.1%, and the modulation depth is 78.7%. Meanwhile, the number of each layer of graphene can be adjusted to achieve high absorption bandwidth, relative bandwidth, and modulation depth. Besides, due to the tunable chemical potential of graphene, the absorption coefficient can be adjusted to make up the manufacturing error.

Multiband Polarization Insensitive and Tunable Terahertz Metamaterial Perfect Absorber Based on The Heterogeneous Structure of Graphene

“…Absorbers that use metamaterials in their design and have absorption close to 100% are called metamaterial perfect absorbers (MPA) [23][24][25][26]. There are two types of absorbers: resonant absorbers [27][28][29] and wideband absorbers [30][31][32]. Terahertz band absorbers have many applications such as sensing, imaging, modulating, detection, filtering, etc.…”

Flexible CNT-MXene-CNT Film with Low Surface Conductance for High- and Low-Power Electromagnetic Absorption Protection

“…Extensive use of various new technologies on the battlefield poses serious threats to our military information security. , On the other hand, with the continuous progress of terahertz (THz) generation and modulation technology, high-power electromagnetic weapons have officially moved from the GHz band (0.3–300 GHz) to the THz band (0.1–10 THz) . They are widely used in 6G communications, satellite communications, and short-distance optical fiber-combined encrypted transmission . However, the electronic devices working in this band are more sensitive to strong electromagnetic shocks.…”

Random Graphene Metasurfaces: Diffraction Theory and Giant Broadband Absorptivity

“…A wide absorption bandwidth is achievable in a multilayer system with embedded graphene sheet [14], with the perfect absorption for specific incident angle and layer thickness. The broadband absorption in the THz range can also be realized in the planar structures composed of five layers of graphene due to modulation of the graphene chemical potential [15], as well as in singular graphene gratings [16]. Subwavelength periodicity of metasurfaces is advantageous from the fabrication and theoretical modelling perspectives, but not necessary.…”