摘要
提出了一种结构简单的广角稳定太赫兹可调谐超表面吸波器,利用液晶材料电可调谐的性质,实现超表面吸波器吸收频率的调谐。利用液晶材料介电常数张量进行材料建模,模拟了液晶材料的各向异性特性。为了提高设计效率,得到良好的吸波性能和可调谐性能,利用粒子群算法对超表面吸波器单元结构进行了逆向设计;并对设计的超表面吸波器特性进行研究。结果表明,利用粒子群算法可以高效地逆向设计出性能良好超表面吸波器,当对吸波器施加的电压在0~10 V范围内连续调谐时,实现了TE模式吸波频率在404.4~444.4 GHz范围内连续可调谐,频率可调谐性为9%,吸收率大于99%;TM模式吸波频率在404.4~425.4 GHz范围内连续可调谐,频率可调谐性为4.64%,吸收率大于99%;当斜入射角度为60°时,吸收率仍大于94%,具有大角度入射稳定性和吸收频率稳定性。本文设计的太赫兹超表面吸波器具备高吸收率、大频率可调谐性、广角稳定性和低控制电压等优点,具有广泛的应用价值。
Recently,metasurfaces have received widespread attention due to their unique properties and potential applications in many fields such as biosensing,imaging,and communication.Among these studies,metasurface absorbers have aroused much interest of researchers.Absorbers can perfectly absorb incident certain frequencies or some frequencies of electromagnetic waves,and are widely used in fields such as electromagnetic compatibility and electromagnetic shielding.Compared with traditional absorber materials,a metasurface absorber overcomes the disadvantages of large volume,heavy weight,and poor stability.To cope with diverse application scenarios,it is essential to achieve frequency tunability of a metasurface absorber.In this paper,we propose a liquid crystal-based tunable terahertz metasurface absorber with the advantages of simple structure,and wide-angle stability.By utilizing the electrically tunable property of liquid crystal materials,the absorption frequency of the metasurface absorber can be tuned.Using the dielectric constant tensor of liquid crystal materials for material modeling,the anisotropic properties of liquid crystal materials were simulated.To improve the design efficiency and achieve good absorption and tunability performance,the Particle Swarm Algorithm(PSO)was used for reverse design of the parameters of the meta-surface unit structure.We investigated the absorption characteristics,frequency tunability,and polarization characteristics of the meta-surface absorber obtained by reverse design under vertical incidence,as well as the electromagnetic wave absorption characteristics at different incident angles.The results show that the absorbers with good absorption and tunability performance can be reverse designed efficiently by PSO. By applying voltage to the metasurface absorber obtained by reverse design,and continuously tuning the voltage in the range of 0~10 V, the TE mode absorption frequency iscontinuously tunable in the range of 404.4~444.4 GHz, with a frequency tunability of 9%. The TM modea
作者
井越洋
李培丽
张亚杰
曹阳
陈羽
JING Yueyang;LI Peili;ZHANG Yajie;CAO Yang;CHEN Yu(College of Electronic and Optical Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210023,China)
出处
《光子学报》
EI
CAS
CSCD
北大核心
2023年第10期228-238,共11页
Acta Photonica Sinica
基金
武汉光电国家研究中心2022年度开放基金(No.2022WNLOKF012)
江苏省研究生科研创新计划(Nos.KYCX22_0909,KYCX22_0989)。
关键词
液晶
超表面
粒子群优化
可调谐
吸波器
Liquid crystal
Metasurface
Particle swarm optimization
Tunable
Absorber
