Dual-Band Terahertz Beam Splitter Based on Polarization-Dependent Metasurfaces

In this letter, a dual-band transmission-reflection-integrated coding metasurface is proposed. It possesses frequency- and polarization-dependent properties and is capable of effectively generating and controlling splitting beam patterns. The multilayered coding unit mainly consists of a multistrip layer, a double arrow layer, and metal gratings along two ortho- gonal directions. Unlike individually reflective or transmissive metasurfaces that operate at only a single frequency point, the proposed metasurface can realize reflected and transmitted beam-splitting patterns under vertically polarized and horizontally polarized incident plane waves at both 135 GHz and 225 GHz, respectively. The proposed metasurface can independently realize different beam-splitting patterns by using corresponding coding sequences at two separate frequencies. For demonstration, the proposed metasurface is fabricated and measured, showing a reasonable agreement with simulated results.

I. Introduction

In recent years, terahertz (THz) band has attracted much attention for its rich and untapped spectral resources [1]. With characteristics such as broadband, nonionizing low-energy and high penetration through various dielectric materials, THz waves have broad application prospects [2].