A novel analytical method for designing a multi-band, polarization-insensitive and wide angle graphene-based THz absorber

Circuit modeling of ultra‐broadband terahertz absorber based on graphene array periodic disks

“…14,28 However, the best achieved normalized bandwidth of absorption over 90% to the central frequency of 1 and 2 THz is 98% and 88%, respectively. 14 In other works 14,[19][20][21][22][23][24][25] in which the device has been designed for achieving broadband or ultrabroadband absorption, this number is less than the best reported work. Khavasi 14 indicates that the design of ultrabroadband absorption in a higher frequency of THz spectra has some limitations, and it is not a simple task.…”

“…[6][7][8][9][10][11][12] However, the requirement of some applications is tunable narrowband THz absorbers, 13 while the requirement of the others is ultra-broadband absorbers, 14,15 and research in this area is ongoing. [16][17][18] Various geometrical structures including circular patches, 19 ring arrays, 20 graphene stacks, 21,22 rectangular fish-scale, 23 cascade metal-dielectric pairs, 24 and specific ring resonator 25 have been proposed to achieve ultra-wideband or broadband absorption. However, with all the works that have been down, providing a simple design approach to increase bandwidth along with fabrication issues is still challenging.…”

“…As a numerical example, we design an ultra-broadband absorber with the absorption over 121% for the central frequency of 1.66 THz, which is significantly larger than the best previous works. 14,[19][20][21][22][23][24][25] In addition, the proposed structure is really simple and can be manufactured by current manufacturing techniques like chemical vapor deposition (CVD). The remainder of this paper is organized as follows: In Section 2, the proposed structure is described, and the circuit model of the structure and the design approach are presented.…”

“…In this work, we propose an ultra‐broadband absorption design that is simple but robust. As a numerical example, we design an ultra‐broadband absorber with the absorption over 121% for the central frequency of 1.66 THz, which is significantly larger than the best previous works . In addition, the proposed structure is really simple and can be manufactured by current manufacturing techniques like chemical vapor deposition (CVD).…”

Highly tunable multi‐band THz absorber with circuit model representation using multi‐bias scheme

“…In this article, a temperature of T = 300 K (room temperature) and τ = 0.5 ps are assumed. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] Here in this work, a modified circuit model approach is used to describe layers exploiting developed circuit representation in Reference 26. According to References 26-30, periodic arrays of Nano-disks can be modeled via passive circuit elements while physical features and technology dependents parameters are embedded in-circuit elements.…”