Tunable GRIN lensing based on graphene-dielectric multilayer metamaterials

Abstract

In this paper, we have proposed effective gradient refractive index structures at terahertz frequencies, which function as a planar lens, focusing reflector, and a generalized Luneburg lens (GLL). We base the structures on planar and cylindrical graphene-dielectric multilayer metamaterials. The structures are designed by tailoring the surface conductivity of the graphene layers to provide a given phase profile along with the structures. Therefore, the customizable focus area of the focusing devices, and the tunable terahertz jet effect that is produced by the GLL result. The proposed structures have potential applications in terahertz imaging, sensing, detecting, and communication areas.

Nonlinear eigenvalue problems for coupled Helmholtz equations modeling gradient-index graphene waveguides

“…Optical properties of cylindrical waveguides with graphene interfaces have been extensively studied in the engineering community [3,14,15,16]. Recently, focus has also shifted to gradient-index structures that couple with graphene [17,18]. These structures are based on planar and cylindrical graphene-dielectric multilayer metamaterials, and have shown potential applications in terahertz imaging, sensing, detecting, and communication areas [17,18].…”

“…Recently, focus has also shifted to gradient-index structures that couple with graphene [17,18]. These structures are based on planar and cylindrical graphene-dielectric multilayer metamaterials, and have shown potential applications in terahertz imaging, sensing, detecting, and communication areas [17,18]. Numerical methods that compute eigenvalues of inhomogeneously loaded domains have been studied before [19,20,21,22].…”

“…Eigenvalues from (L) Eigenvalues from (Q) Eigenvalues from (18) Mode kz kz kz 1 9.447 ± 0.090468i 9.447 ± 0.090467i 9.447 ± 0.090467i 2 13.00 ± 0.090641i 13.00 ± 0.090640i 13.00 ± 0.090641i 3 16.17 ± 0.099812i 16.17 ± 0.099812i 16.17 ± 0.099813i…”