基于偏振不敏感超材料的全光可调谐太赫兹慢光效应研究  

Study on all-optical tunable terahertz slow-light effects based on polarization-insensitive metamaterials

作　　者：金嘉升 马成举[1] 张垚 张跃斌 鲍士仟 李咪 JIN Jiasheng;MA Chengju;ZHANG Yao;ZHANG Yuebin;BAO Shiqian;LI Mi(School of Science,Xi'an Shiyou University,Xi'an,Shaanxi,710065,China)

机构地区：[1]西安石油大学理学院,陕西西安710065

出　　处：《光电子．激光》2023年第12期1263-1270,共8页Journal of Optoelectronics·Laser

基　　金：西安石油大学创新与实践能力培养项目(YCS20213210)资助项目。

摘　　要：太赫兹(terahertz, THz)慢光效应可以有效地提升THz脉冲数据传输的安全性和存储性,而一般THz慢光器件对入射THz波偏振态变化敏感。本文设计了一种超材料结构,其微结构单元由一个十字型谐振器和4个U型谐振器构成。研究表明:基于超材料的THz慢光效应对线偏振光和圆偏振光均不敏感。通过对超材料结构的参数优化,获得到了最大群折射率为1 618的慢光效应。另外,本文在超材料微结构层和SiO2衬底之间嵌入了一层二硫化钼(MoS_(2))薄膜,当MoS_(2)的载流子浓度从1.7×10^(17)cm^(-3)增大到5.1×10^(19)cm^(-3)时,群折射率从1 566减小到26。实现了偏振不敏感全光可调谐的THz慢光效应。该研究有望为偏振不敏感和全光可调谐的THz慢光器件设计提供崭新的研究思路。The terahertz(THz)slow-light effect can effectively improve the security and memory property of THz pulse data during transmission.However,the general THz slow-light devices are sensitive to the polarization state changing of the incident THz wave.In this paper,we design a metamaterial structure whose unit cell consists of one cross resonator and four U-shaped resonators.The results show that the THz slow-light effects based on metamaterials are not sensitive to both linear and circularly polarized light.A slow-light effect with the maximum group refractive index of 1618 is obtained by optimizing parameters of the metamaterial structure.A molybdenum disulfide film between the metamaterial microstructure layer and the SiO_(2)substrate is embedded.When the carrier concentration of molybdenum disulfide increases from 1.7×10^(17) cm^(-3) to 5.1×10^(19 )cm^(-3),the group refractive index decreases from 1566 to 26,and a polarization insensitive all-light tunable THz slow-light effect is realized.This study can provides some new ideas for the design of polarization insensitive and all-light tunable THz slow-light devices.

关 键 词：超材料 太赫兹(THz) 慢光效应 偏振不敏感 二硫化钼(MoS_(2)) 

分 类 号：O436[机械工程—光学工程] TN91[理学—光学]