Study On Mode Dispersion And Energy Flow Properties In Miro-nano Composite Multilayer Structure

For scientists working in nanophotonics, it is a challenge to control of transmitting and manipulating the optical energy flow on a nonscale, which provides an insightful picture of getting the all-optical divices. Due to the strong confinement and large field enhancement of the SPP wave in miro-nano composite multilayer structure, it will lead to nonlinear effects in the nonlinear-dielectric and has an effect on the optical properties of multilayer structure.In this article, We present the exact dispersion relation and the nonlinear modes for the TM surface plasmon polariton modes of nonlinear waveguide constituted by a nonlinear Kerr medium sandwiched between two metallic slabs or between doublelayer graphene.Considering a TM mode of a loss-less metal/Kerr medium/metal, we can drive exact dispersion relation from the Maxwell’s equation and talk about how nonlinear coefficient has an impact on the dispersion relation. It’s showed that the dispersion curves bend to the part of low frequency as the guided-wave effective index increases. There exit three types of nonlinear modes: symmetric, antisymmetric and asymmetric, and we also display the electromagnetic field distribution of these modes.Substituting graphene for metal, the exact dispersion relations of graphene/Keermedium, graphene/Kerr-medium/graphene are also driven from the Maxwell’s equation, and we analyze about how the nonlinear coefficient influence the the electromagnetic field. It’s indicated that there exist three modes in graphene/Keermedium/graphene: symmetric, antisymmetric and asymmetric and the electromagnetic distributions of these modes are displayed.For energy flow, we find that the evanescent electromagnetic waves forming the surface polariton possess a backward spin energy flow, which, together with a superluminal orbital energy flow, form the total Poynting vector. And we also present the spin energy flow, orbital energy flow and the total energy flow in the waveguide, revealing the relation between modes and energy.