Abstract-High-efficiency Huygens’ metasurface for terahertz wave manipulation

Ruiqiang Zhao, Zheng Zhu, Guohua Dong, Tingting Lv, Yuxiang Li, Chunying Guan, Jinhui Shi, and Han Zhang

https://www.osapublishing.org/ol/abstract.cfm?uri=ol-44-14-3482

A fair amount of theoretical work has shown that Huygens’ metasurfaces well modulate electromagnetic waves by properly designing electrical impedance 𝑍𝑒𝑠$Z_{es}$ and magnetic admittance 𝑌𝑚𝑠$Y_{ms}$; however, the transmissive Huygens’ metasurface is still challenging in the terahertz band. In this work, a transmission-type Huygens’ metasurface with bilayer metallic patches has been proposed and theoretically demonstrated to show a reflectionless phase modulation for a linearly polarized terahertz wave. The simulation results show that the metasurface can achieve 2𝜋$2\pi$ phase coverage, and importantly the phase change can be simply achieved by changing a single geometric parameter of the metamolecule, along with a similar transmission effect. We design a high-efficiency beam deflector to realize an anomalous refraction with an angle of 19.8°. The proposed metasurface will provide a simple and direct way to realize efficient terahertz devices for wavefront manipulation.

© 2019 Optical Society of America

Abstract-Asymmetric transmission of linearly polarized waves in terahertz chiral metamaterials

Shenying Fang1,a), Kang Luan2,a), Hui Feng Ma2, Wenjin Lv1, Yuxiang Li1,b), Zheng Zhu1, Chunying Guan1, Jinhui Shi1,3,b), and Tie Jun Cui

http://aip.scitation.org/doi/abs/10.1063/1.4974477

We experimentally demonstrate the asymmetric transmission of linearly polarized waves in a multilayer chiral metamaterial in the terahertz (THz) regime. The chiral metamaterial is constructed by two stacked orthogonal metallic layers embedded in polyimide dielectric layers. Simulated and measured results show that the proposed multilayer chiral metamaterial can achieve dual-band direction-dependent cross-polarization conversions for both x- and y-polarized THz waves. The polarized wave passing through the metamaterial will be converted into its orthogonal polarization state, while the same polarized wave is blocked along the reversed propagation direction. In addition, the asymmetric transmission band may be effectively engineered to other frequencies by slightly adjusting the gap width. We believe that our findings are beneficial in manipulating the polarization state of THz waves and exploring polarization-sensitive THz devices.