Terahertz Wave Front Manipulation Based on Pancharatnam-Berry Coding Metasurface

We design a coding metasurface based on Pancharatnam-Berry (PB) phase to manipulate terahertz waves, which is simple and flexible. Compared with the previous design of the coding metasurface, the present coding particles can be obtained by using a same size meta-particle with various orientations instead of designing multiple structures or changing specific size parameters. The PB coding metasurfaces composed of U-shaped particles with pre-designed coding sequences can generate multi-bit coding in the terahertz frequencies and control the reflected terahertz waves to the various directions. Both simulation and theoretical calculation scattering patterns of the designed PB coding metasurfaces demonstrate the expected manipulations. Additionally, the bandwidth of radar cross section (RCS) reduction of approaching -15 dB is 1.05THz (range from 0.9THz to 1.95THz). We believe that the proposed design provides a more flexible way for the manipulation of reflected terahertz waves. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement