Multiple Resonances Induced Terahertz Broadband Filtering in a Bilayer Metamaterial

A bilayer metamaterial to realize the broadband transmission in a terahertz (THz) filter was proposed, whose periodic unit structure consists of two rectangular apertures. The consisting three peaks has 3dB range 0.75 THz, which is 1.6 times that monolayer structure. Different from traditional narrow band excitation mode, additional are produced by metamaterials. Sweeping frequency analysis illustrated spacing between layers metamaterials an influence on these peaks. bandwidth ranges can be regulated adjusting at proportional height. In particular, experimental results show proposed excellent selective performance with 0.7 THz 0.79 1.49 THz. This design filtering introducing supplies new approach potential application filter.