Wideband and Tunable Reflective Cross-Polarization Conversion Metasurface for TeraHertz Applications

Abstract

An ultrathin and wideband reflective crosspolarization converter is presented in this paper. The design consists of a pair of modified dumbbell shaped resonators which are connected together with a conductive strip. The proposed single-layer THz metasurface achieved a high polarization conversion ratio (PCR) of ≥95% in the operating frequency ranging from 1.76-4.26 THz. This wide-bandwidth cross-polarization conversion is obtained by exciting multiple closely spaced resonant frequencies at 1.98 THz, 2.61 THz, 2.95 THz, and 3.93 THz. The working mechanism of the proposed structure is analyzed and the polarizer exhibits an excellent angular stability upto 40 0 of incidence. Further, the proposed cross-polarizer exhibits continuous tunability of PCR over the operating frequencies when photoconductive silicon (Si) is filled in the gap between pair of dumbbell-resonators. The wideband characteristics and the switchable property show that the proposed reflective cross polarizer is an excellent candidate for manipulation and control of polarization in THz communication systems.

Tunable Wideband Cylindrical Dielectric Resonator Inspired Metasurface Absorber for Medical Sensing Applications

“…Maximum thickness of dielectric is denoted by H. [ln e ] are the complex conjugate and real conjugate of a complex number. Permittivity (εr) and permeability (μr) of the proposed MS can be extracted by refractive index (n) and z shown in equation (8).…”

“…A novel design of a patterned graphene-based plasmon-induced transparency (PIT) metasurface for absorption and slow-light applications in THz communication has been developed in [7]. Represents an ultrathin and broadband reflective cross-polarization converter by using a single-layer THz metasurface contains a couple of modified dumbbell shaped resonators linked with a conductive strip [8]. The broadband and switchable characteristics covers resonant frequencies of 1.98THz, 2.61THz, 2.95THz, and 3.93THz.…”

Research and Design of a Polarization Multiplexed 1-bit Reconfigurable Metasurface for Dynamic Focusing

“…In order to achieve arbitrary focus trajectory, the reflection phase distributions corresponding to different focuses must be designed to convert the incident electromagnetic wave into the required focused beam. The phase distribution required by the focus can be calculated by formula (1), and the expression of the electric field distribution required on the reflective metasurface [23] is:…”

“…Metasurfaces, as two-dimensional metamaterials, can flexibly control electromagnetic wave properties, such as amplitude, phase, and polarization, so attracted more and more attention from scholars [1,2]. Based on the theory of electromagnetic wave regulation, metasurfaces are widely used in many aspects such as antennas [3], polarization converters [4], perfect absorbers [5], invisibility cloaks [6], and nearfield focusing [7].…”