摘要
太赫兹波在超材料表面结构中会发生电磁响应,使得特定频率的电磁波发生反射与透射。利用VO2的相变特性,设计了一种基于超材料的可调谐三信道太赫兹分波器。采用Drude模型,分析了该分波器两种状态下的仿真S参数曲线、等效参数曲线和群延迟曲线,并研究了分波器的工作机理。处于通信窗口的0.30、0.46、0.50 THz太赫兹波实现了分离,分波器的隔离度均大于22 dB,插入损耗均小于0.40 dB,群延迟低且性能指标受参数变化的影响较小,满足工作性能的设计要求。与传统的光子晶体和绝缘硅分波器相比,所设计的分波器具有隔离度高和插入损耗低等特点。与超材料二信道分波器相比,所设计的分波器提高了信道容量,实现了信道可调谐功能。所设计的分波器在太赫兹无线通信波分复用系统中,展现出实现多信道传输的潜力,具有较好的应用前景。
Objective Terahertz radiation yields electromagnetic responses when interacting with metamaterials,thus resulting in the reflection and transmission at specific frequencies.Currently,studies regarding terahertz demultiplexers based on metamaterials are few;most studies focus on photonic crystals and insulated silicon demultiplexers.However,photonic-crystal fabrication is challenging and expensive,which hinders its large-scale implementation.Silicon has a large thermo-optic coefficient,which changes the refractive index significantly even under slight environmental temperature variations,thus causing shifts in the center frequency.Moreover,the existing metamaterial demultiplexers can only achieve two-channel demultiplexing.Therefore,this study proposes a tunable threechannel terahertz demultiplexer based on metamaterials that utilizes the phase-transition characteristics of VO2.By employing the Drude model,we obtain simulated S parameters and the equivalent parameters,as well as analyze the group delay curves for two states.Subsequently,we analyze the operating mechanism of the demultiplexer.The proposed demultiplexer exhibits wave separation at 0.30,0.46,and 0.50 THz within the communication window.Additionally,it exhibits isolation exceeding 22 dB,insertion losses of less than 0.40 dB,low group delays,and minimal sensitivity of performance indicators to parameter variations,thus satisfying the design requirements for operational performance.Compared with conventional photonic crystals and insulated silicon demultiplexers,the proposed demultiplexer exhibits higher isolation and lower insertion loss.Meanwhile,compared with existing metamaterial demultiplexers,it offers higher channel capacities and enables channel tunability.Its application prospects include multichannel transmission in terahertz wireless-communication wavelength-division multiplexing systems.Methods The metamaterial unit cell comprises an upper metal square ring and a metal line,an intermediate dielectric layer of polyimide,and a bottom VO2 recta
作者
马勇
郑佐月
黎人溥
郭晓越
张振
郭俊启
Ma Yong;Zheng Zuoyue;Li Renpu;Guo Xiaoyue;Zhang Zhen;Guo Junqi(College of Optoelectronic Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2024年第18期217-224,共8页
Chinese Journal of Lasers
基金
新一代信息网络与终端省部共建协同创新中心项目
中电科芯片技术(集团)有限公司量子实验室基金(6310001-2)
重庆邮电大学交叉学科和新兴领域重点专项项目(A2018-01)
重庆市基础与前沿研究项目(cstc2016jcyjA0301)
2021年度重庆市留学人员创业创新支持计划(cx2021011)
国家自然科学基金青年基金(61405001).
