Abstract-Terahertz planar lenses based on plasmonic metasurfaces

Chang Yang, Yun Shen, Yanqiang Xie, Qi Zhou, Xiaohua Deng, Juncheng Cao,


https://www.sciencedirect.com/science/article/abs/pii/S037596011831185X


Plasmonic planar lenses on silicon substrate are designed to realize terahertz (THz) wave focusing. Super-unit-cells containing eight different resonant units are presented to construct eight concentric rings on the silicon substrate. By controlling of the position distribution of the resonant units, it is shown that focusing at 4.3 THz can be achieved. Moreover, due to that the eight units can steer THz wave and keep phase gradient in frequency range of 4.2 to 4.5 THz, the metalenses can realize broadband THz focusing. The results imply the potential applications in THz wave control devices of light collection and multi-channel optical communication.

Abstract-Terahertz unidirectional invisibility in grating-based structures

Tao Wang, Liner Zou, Yun Shen, Miao Yi, Xiaohua Deng

http://www.tandfonline.com/doi/abs/10.1080/09500340.2017.1330973?journalCode=tmop20

A grating-based structure is proposed to realize unidirectional invisibility in the terahertz range. We show that the strict demand on refractive index for unidirectional invisibility can be flexibly satisfied in such proposed structure due to the tunable effective refractive index property of the grating layer by adjusting its geometric parameters. All these behaviours are demonstrated in the example of GaAs grating-based structure illuminated around 40 μm. Our results may lead to the development of a variety of novel terahertz devices for photonic integrated circuits.