Affiliation:
1. THz Technical Research Center of Shenzhen University, Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
2. Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China
Abstract
Achieving perfect absorption of electromagnetic waves across a wide range of frequencies is crucial for various applications, including sensing, imaging, and energy capture. In this study, we introduced a new concept for metasurfaces and proposed a six-layer vertically structured IGIGIM metasurface consisting of gold (Au), silicon (Si), graphene (G1), silica (SiO2), a second layer of graphene (G2), and polymethyl methacrylate (PMMA), which demonstrates ultra-wideband absorptance in the terahertz (THz) region. Through theoretical analysis and numerical simulations, we obtained broadband absorptance over 80% with the average absorptance of 92.6% and a bandwidth of 8.22 THz, from 1.78 to 10.0 THz. Whereas, dual broadband absorptance was obtained for above 90% with the bandwidth of 5.63 THz in the two sub-bands of 2.09–3.5 THz and 5.78–10 THz and above 95% with the bandwidth of 3.63 THz in the two sub-bands of 2.32–3.12 THz and 6.35–9.9 THz. Moreover, the proposed structure exhibits a polarization-independent absorption property. Also, it demonstrates a tolerance for the incident angle of 40 degrees, maintaining a wide absorption band. This remarkable feature is attributed to the multiple Fabry–Pérot resonance absorptions in the structure. Our study presents a convenient method for designing high-quality terahertz wave absorbers with outstanding broadband absorptance.
Funder
Shenzhen Science and Technology Project
Guangdong Province Natural Science Funds
Subject
Inorganic Chemistry,Condensed Matter Physics,General Materials Science,General Chemical Engineering