Giant enhancement of tunable asymmetric transmission for circularly polarized waves in a double-layer graphene chiral metasurface

Abstract

In this paper, we propose a structure based on double-layer graphene-based planar chiral metasurface with J-shaped pattern to generate asymmetric transmission, which can reach to 16.64%.

Dispersion Theory of Surface Plasmon Polaritons on Bilayer Graphene Metasurfaces

“…The dispersion characteristic change in GSP mode is more sensitive by changing graphene ribbon width compared to the variation in gap size for the given structure. This also suggests that changing graphene ribbon width is more effective for creating some gradient-index metadevices where the full phase coverage is needed, such as high-efficiency couplers, meta-lenses, and enhanced emitters [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ]. The analytic dispersion expressions are very useful to analyze its propagating characteristic and can also be directly used to design some novel graphene devices where its principle is to heavily rely on software simulations [ 49 , 50 , 51 , 52 ].…”

“…The obtained concise dispersion equations with frequency-wave vector relation include some structural and material parameters and, thus, provide a simple yet useful tool to analyze the basic propagation properties of GSP mode on double-layer graphene metasurfaces in Figure 1 . Further, they can also be readily used to develop some novel functional devices [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ] if the specific dispersion diagrams are calculated.…”

“…The dispersion expression and mode distribution are simple for the single graphene metasurface [ 44 , 47 ]. Very recently, some functional plasmonic devices have also been designed on double-layer graphene metasurfaces in [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ]. Compared to single-layer graphene metasurface, a double-layer structure can provide more degrees of freedom to control GSPs and, thus, may be more advantageous than a single-layer structure [ 52 , 53 , 54 ].…”

“…Very recently, some functional plasmonic devices have also been designed on double-layer graphene metasurfaces in [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ]. Compared to single-layer graphene metasurface, a double-layer structure can provide more degrees of freedom to control GSPs and, thus, may be more advantageous than a single-layer structure [ 52 , 53 , 54 ]. However, its fundamental dispersion theory and the detailed GSPs’ mode distributions with various parameters are not reported so far because of its complicated periodical boundary conditions.…”

Symmetric accelerating beam generationviaall-dielectric metasurfaces

“…By the virtue of subwavelength nano-resonators (unit cells), metasurfaces can tailor the polarization, phase, and amplitude of impinging light to generate high-quality accelerating beam and overcome the limitations imposed by the SLM. Furthermore, several exotic phenomena have been realized through metasurfaces, such as hologram, 6,7 meta-lens, 8,9 optical vortex, 10 meta-polarizer, [11][12][13] sensing, 14 and beam splitter. 11,15 Recently, numerous metasurfaces have been proposed to demonstrate the accelerating beam generation.…”