Tunable dual-frequency cross polarization converters based on graphene metasurface in infrared range

Abstract

A tunable dual-frequency metamaterial graphene polarization converter in the infrared range is put forward in this paper. The proposed converter is made up of 3 layers—the bottom gold layer, the middle silicon dioxide layer and the upper graphene layer. The simulated results show that the polarization converter can simultaneously work at two resonant frequencies of 36.82 and 41.38 THz. The polarization conversion rates are up to 0.9992 at 36.82 THz and 0.9969 at 41.38 THz under the certain normal condition when Fermi energy is given to 1.0 eV, showing the high efficiency of the polarization converter. Moreover, the converter shows its stable working performance under the change of the incident angle and the geometrical size. Meanwhile, without varying the nanostructure, the resonant frequencies can be flexibly adjusted by controlling the Fermi energy. The superior performance of the proposed graphene polarization converter indicates a broad prospect that a large number of applications such as infrared imaging sensors, modulators, switches, photonic and biochemical sensors, light harvesting, thermal detection and electromagnetic energy converter will apply it.

Optimized chemical potential graphene-based coding metasurface approach for dynamic manipulation of terahertz wavefront

“…By electrostatic or magnetostatic biasing or by chemical doping, EM characteristic of graphene can be controlled [32]. Moreover, because of having a strong interaction with EM waves, graphene can be used in diverse applications such as plasmonic antennas [33,34], polarization converters [35], absorber [36], and THz wave manipulation [37][38][39][40]. The chemical potential is the most important parameter in graphene tunability, and based on the Kubo formula surface impedance of graphene monolayer is depended on its chemical potential, which can be controlled by an applied electrostatic field.…”

Terahertz Multi-Band Absorber and Dual-Bandwidth Polarization Converter Based on Vo2 and Graphene

“…Graphene, a two-dimensional material with honeycomb lattice, has a surface conductivity that could be dynamically adjusted by applying external voltage or chemical doping to it [26]. Correspondingly, electromagnetic devices using graphene as tuning medium have been frequently reported [27][28][29][30][31][32][33]. In 2019, Wang et al [27] proposed a structure of a polarization converter that can realize cross-polarization conversion.…”

“…Correspondingly, electromagnetic devices using graphene as tuning medium have been frequently reported [27][28][29][30][31][32][33]. In 2019, Wang et al [27] proposed a structure of a polarization converter that can realize cross-polarization conversion. The designed polarization converter uses graphene as the main material to realize the dynamic tuning of conversion efficiency, which makes conversion efficiency even reach 0.99.…”

T-shaped reflective polarizer under second Bragg incidence

“…The polarizer [1][2][3][4][5] can split the incident light into two mutually orthogonal polarized lights, which plays an important role in the field of terahertz devices [6], infrared telecom [7], information technology [8], information processing [9][10][11], imaging [12][13][14][15], optical storage [16][17][18][19], and polarization detection of light [20][21][22][23]. The conventional polarization separators are usually based on the birefringence of crystal, and the size is generally in the order of millimeter.…”