Chinese Optics Letters, Vol. 17, Issue 4, 041602 (2019)
Arbitrary linear THz wave polarization converter with cracked cross meta-surface
Han Sun1, Lan Wang1,*, Yaxin Zhang1,**, Shixiong Liang2, Jiaguang Han3, Feng Lan1, Xinlan Zhou1, and Ziqiang Yang1
- 1Terahertz Science and Technology Research Center, University of Electronic Science and Technology of China, Chengdu 610054, China
- 2National Key Laboratory of Application Specific Integrated Circuit, Hebei Semiconductor Research Institute, Shijiazhuang 050051, China
- 3Center for Terahertz Waves, College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Key Laboratory of Optoelectronic Information Technology, Ministry of Education, Tianjin 300072, China
This Letter presents a double-layer structure combining a cracked cross meta-surface and grating surface to realize arbitrary incident linear terahertz (THz) wave polarization conversion. The arbitrary incident linear polarization THz wave will be induced with the same resonant modes in the unit cell, which results in polarization conversion insensitive to the linear polarization angle. Moreover, the zigzag-shaped resonant surface current leads to a strong magnetic resonance between the meta-surface and gratings, which enhances the conversion efficiency. The experimental results show that a more than 70% conversion rate can be achieved under arbitrary linear polarization within a wide frequency band. Moreover, around 0.89 THz nearly perfect polarization conversion is realized.