基于人工表面等离激元周期调制的漏波天线设计

基于超薄波纹金属条带结构,利用人工表面等离激元的周期调制原理,设计出辐射波束角度及数量均可设计的漏波天线.首先,分析了不同周期下人工表面等离激元单元结构的色散特性;其次,介绍了周期调制的原理,即通过将调制周期从亚波长尺寸不断增大到波长尺寸,人工表面等离激元将经历从高效传输到截止,然后到定向漏波乃至多波束辐射的过程;再次...     

Transmissive 2-bit anisotropic coding metasurface

Coding metasurfaces have attracted tremendous interests due to unique capabilities of manipulating electromagnetic wave. However, archiving transmissive coding metasurface is still challenging. Here we propose a transmissive anisotropic coding metasurface that enables the independent control of two orthogonal polarizations. The polarization beam splitter and the orbital angular momentum (OAM) generator have been studied as typical applications of the anisotropic 2-bit coding metasurface. The simulated far field patterns illustrate that the x and y polarized electromagnetic waves are deflected into two different directions, respectively. The anisotropic coding metasurface has been experimentally verified to realize an OAM beam with l = 2 of right-handed polarized wave, resulting from both contributions from linear-to-circular polarization conversion and the phase profile modulation. This work is beneficial to enrich the polarization manipulation field and develop transmissive coding metasurfaces.