3 November 2016 Terahertz beam shaping with metasurface
Author Affiliations +
Abstract
Based on metasurface, two beam shapers are designed to modulate the wavefront of the terahertz beam. One of the beam shapers is THz ring-Airy beam generator and the other is THz four-focus lens. Each beam shaper is composed of a serious of C-shaped slot antennas, which can be used to modulate the phase and amplitude of the cross-polarized scattered wave. A THz holographic imaging system is utilized to measure the field of the generated beams. The ring- Airy beam shaper is designed by replacing both the phase and amplitude of its initial electric field with the corresponding antennas. In the experiment, an abrupt focus following a parabolic trajectory is subsequently observed. This method can be expanded to other wavebands, such as the visible band, in which the ring-Airy beam shaper can replace traditional computer-generated holography to avoid undesirable multiple diffraction orders. The phase distribution of the four-focus lens is obtained by using the Yang-Gu amplitude-phase retrieval algorithm and then encoded to the antennas. Both the focusing and imaging properties are demonstrated. A clear image can be obtained with a bandwidth of 110 GHz. This type of transmissive metasurface beam shaper serves as an attractive alternative to conventional diffractive optical elements based on its small size, ease of fabrication, and low cost.
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jingwen He, Jingwen He, Sen Wang, Sen Wang, Yan Zhang, Yan Zhang, } "Terahertz beam shaping with metasurface", Proc. SPIE 10030, Infrared, Millimeter-Wave, and Terahertz Technologies IV, 1003019 (3 November 2016); doi: 10.1117/12.2246988; https://doi.org/10.1117/12.2246988
PROCEEDINGS
6 PAGES


SHARE
RELATED CONTENT

Precise holograms using complex light modulation
Proceedings of SPIE (March 06 2014)
Optical design of CCAT
Proceedings of SPIE (June 22 2006)
Terahertz super thin planar lenses
Proceedings of SPIE (December 04 2012)

Back to Top