凹槽修饰的太赫兹亚波长狭缝透射特性  

Transmission characteristics of groove modified Terahertz subwavelength slit

作　　者：孙书超 孟阔[1] SUN Shuchao;MENG Kuo(School of Instrument Science and Optelectronics Engineering,Beijing Information Science&Technology University,Beijing 100192,China)

机构地区：[1]北京信息科技大学仪器科学与光电工程学院,北京100192

出　　处：《北京信息科技大学学报（自然科学版）》2023年第5期67-73,87,共8页Journal of Beijing Information Science and Technology University

基　　金：北京市自然科学基金(4184087)。

摘　　要：为研究太赫兹波通过亚波长金属结构产生异常透射增强现象的规律,以凹槽修饰狭缝内壁的亚波长结构模型为基础,对太赫兹波段下Cu金属狭缝透射特性进行研究。依据表面等离子体理论,利用时域有限差分法对结构模型进行仿真分析。通过改变凹槽结构的几何形状,如深度、宽度、周期等参量,研究亚波长结构特征对太赫兹波透射特征调制的变化规律。研究发现,随狭缝内壁双面刻蚀矩形凹槽数目或深度的增加,太赫兹波透射明显增强,低频波段透射峰发生强度增强和峰位偏移;凹槽对称排布以及错位排布均对透射光谱有明显的调制作用。研究结果对金属亚波长结构的优化设计和新型太赫兹波功能器件的研发具有参考价值。In order to obtain the law of abnormal transmission enhancement of terahertz wave through subwavelength metal structure,the transmission characteristics of Cu metal slit in terahertz band were studied based on the sub-wavelength structure model with groove modified slit inner wall.According to the surface plasma theory,the structure model was simulated and analyzed by finite-difference time-domain(FDTD)method.By changing the geometry of the groove structure,including depth,width,period and other parameters,the change law of subwavelength structure features on the transmission characteristics of terahertz waves was studied.The experimental results show that,with the increase of the number or depth of rectangular grooves engraved on both sides of the inner wall of the slit,the terahertz wave transmission is significantly enhanced and peak intensity enhancement and position shifting occurs in low frequency band.Groove symmetrical arrangement or dislocation arrangement has obvious modulation effects on the transmission spectrum.The research results are valuable for the optimization design of metal subwavelength structures and the development of new terahertz functional devices.

关 键 词：太赫兹 表面等离子光子学 亚波长结构 时域有限差分法 

分 类 号：O44[理学—电磁学]