Wu Guozhang, Jiao Xiaofei, Wang Yuandong, Zhao Zeping, Wang Yibo, Liu Jianguo
Opt Express. 2021 Jan 18;29(2):2703-2711. doi: 10.1364/OE.416227.
A dynamically adjustable ultra-wideband metamaterial perfect absorber (MPA) is proposed which consists of three resonance rings based on vanadium dioxide (VO) and a metal ground layer separated by a dielectric spacer. The simulation results show that the terahertz (THz) absorption bandwidth of more than 90% absorptance reaches 3.30 THz, which covers from 2.34 to 5.64 THz, under different incident polarization angles. The range is better than that of previous VO-based reports. Moreover, when the conductivity of VO changes from 200 S/m to 2×10 S/m, the absorption peak intensity can be adjusted continuously from 4% to 100%. The key is to optimize the geometric structure through interference cancellation and impedance matching theory, to achieve better absorption bandwidth and efficiency. Besides, the terahertz absorber has a wide-angle absorption effect both in TE and TM waves. Thus, the designed absorber may have many potential applications in modulating, sensing and imaging technology.
提出了一种动态可调的超宽带超材料完美吸收器（MPA），它由基于二氧化钒（VO）的三个谐振环和一个通过电介质间隔层与金属接地层隔开的结构组成。仿真结果表明，在不同入射偏振角下，吸收率超过90%的太赫兹（THz）吸收带宽达到3.30 THz，覆盖范围为2.34至5.64 THz。该范围优于先前基于VO的报道。此外，当VO的电导率从200 S/m变化到2×10 S/m时，吸收峰强度可以从4%连续调节到100%。关键在于通过干扰消除和阻抗匹配理论优化几何结构，以实现更好的吸收带宽和效率。此外，太赫兹吸收器在TE波和TM波中均具有广角吸收效应。因此，所设计的吸收器在调制、传感和成像技术中可能具有许多潜在应用。
