A Chiral Metasurface‐Based Broadband Terahertz Perfect Absorption Device
Zan Li, Hua Yang, Lianbao Jia, Zao Yi, Shubo Cheng, Chaojun Tang, Juan Deng, Boxun Li
Abstract
This study proposes a broadband terahertz perfect absorber based on a metasurface, with its innovation lying in its simple structure and independence from complex materials, effectively addressing the technical challenges associated with the synthesis and processing of complex materials in traditional absorbers. This concise design not only reduces fabrication difficulty but also achieves exceptional absorption performance. Simulation results demonstrate that the absorber exhibits an absorption bandwidth of 2.28 THz, with an average absorption rate exceeding 98.9% within the operational frequency range of 8.8 to 10.62 THz, and a peak absorption rate reaching up to 99.72%. Furthermore, owing to its chiral symmetry, the absorber shows excellent polarization insensitivity, maintaining stable absorption performance under terahertz wave incidence at various polarization angles. This feature ensures its flexibility in practical applications. Through simulation methods, the electric field distribution characteristics of the absorber were further analyzed, and the physical mechanism behind its high absorption efficiency was revealed by combining impedance matching theory. The study found that the surface‐patterned Au layer can excite localized surface plasmon resonance effects, enabling strong absorption in the terahertz band. Finally, we systematically analyzed the geometric parameters of the absorber and optimized the structural parameters to achieve optimal absorption performance.