Design of multilayer graphene metamaterials plasmonic waveguides with ultra-low-loss mid-infrared

In this the paper, a multilayer graphene metamaterials plasmonic waveguide (MGMPW) with ultra-low-loss has proposed in mid-infrared range. The MGMPW structure consisting of a porous ${\mathrm{SiO}}_2$ stratum placed between multilayer graphene metamaterials with low index dielectric, and a high index dielectric nano-rib geometry, which both placed on a Magnesium fluoride $\left({\mathrm{MgF}}_2\right)$ substrate. The surface plasmon polaritons (SPPs) modes are supported by the multilayer graphene metamaterials with coupling plasmon polaritons at separate graphene layers over the high index dielectric nano-rib structure. Thus, the energy density in the proposed waveguide hardly confined in the area between the high index dielectric nano-edge Aluminum Oxide (${\mathrm{Al}}_2{O}_3$) and the multilayer graphene metamaterials. In the designed waveguide SPPs mode can be obtained the propagation length of nearly 100 µm and the normalized mode area of $\sim {10}^{-7}$ by tunning the values of the waveguide geometry and material parameters. The modal properties of the MGMPW are simulated using technique of the finite element. The dependence of modal characteristics is obtained on the wavelength of incident light, the graphene Fermi energy, and the dimensions of the waveguide geometry in detail. Furthermore, the crosstalk between two adjoining proposed structure is studied to show the SPPs strong squeeze to apply components of photonic integrated circuits.