利用介质超材料控制太赫兹波的振幅和相位  

Simultaneous control of terahertz amplitude and phase with dielectric metamaterials

作　　者：张学迁[1] 张慧芳[1] 田震[1] 谷建强[1] 欧阳春梅[1] 路鑫超[2] 韩家广[1] 张伟力[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院光电信息技术科学教育部重点实验室天津大学太赫兹波研究中心,天津300072 [2]中国科学院微电子研究所,北京100029

出　　处：《红外与激光工程》2016年第4期68-73,共6页Infrared and Laser Engineering

基　　金：国家重点基础研究发展计划(2014CB339800);国家自然科学基金(61427814;61138001;61205098;61422509);高等学校博士学科点专项科研基金(20110032120058)

摘　　要：设计了基于介质高阻硅的超材料用于对太赫兹波的透射振幅和相位进行控制。这里组成超材料的基本结构单元为亚波长柱状硅,相比于基于金属的超材料,其损耗小,效率也更高。太赫兹入射到不同尺寸和旋向的柱状硅时,所透射的太赫兹波的振幅和相位也不同。通过设计不同空间位置处的柱状硅尺寸和旋向,就可以实现任意的振幅和相位分布,从而对透射波波前进行完全的控制。实验中,利用这种硅质微结构设计了三种不同的奇异光栅,其衍射级次和数目可任意控制。这种基于介质超材料的方法,设计简单,加工方便,在制作太赫兹波段低损耗的功能器件方面有着广泛的应用前景。Dielectric metamaterials based on high-impedance silicon were designed for controlling the amplitude and phase of the terahertz waves. Here, the basic unit cells of the dielectric metamaterials are subwavelength silicon pillars, they have lower loss and thus have higher efficiency compared with the metal based metamaterials. As different silicon pillars with different geometric parameters and orientation angles will have different transmission amplitude and phase when the terahertz wave passes through them, nearly arbitrary spatial amplitude and phase distributions can be achieved by designing the geometric parameters and orientation angles of the silicon pillars at different positions, which allows to fully control the shape of the transmitted terahertz wavefront. In experiment, three different meta-gratings were designed using the silicon based structures in which the diffractive orders and their numbers can be arbitrarily controlled. Such dielectric metamaterials are very easy to design and fabricate, making them very promising in developing low-loss terahertz functional devices.

关 键 词：振幅和相位控制 介质超材料 太赫兹 奇异光栅 

分 类 号：O433[机械工程—光学工程]