Controllable Excitation of Surface Plasmon Polaritons in Graphene‐Based Semiconductor Quantum Dot Waveguides

Abstract

AbstractThe research aim of this study is the development of a theoretical semiclassical model of the controllable excitation and propagation of surface plasmon polaritons (SPPs) in planar graphene waveguides by the application of external voltage. The model is based on the numerical solution of the SPP's dispersion equation formulated for a system including two coupled graphene sheets with embedded quantum dots. Using the developed model, the different near‐field patterns realized in the waveguides depending on the quantum dots' ordering and an external voltage applied independently to each graphene sheet with additional gold electrodes are numerically investigated. The obtained results show that the application of external voltage can locally change the chemical potential of graphene and, thereby, lead to controllable excitation of SPPs in the corresponding graphene waveguide. Furthermore, we revealed that the propagation direction of the excited SPPs is determined by the geometrical configurations of the gold electrodes that provide the required SPP routing. The investigated system offers new opportunities for near‐field energy transport and concentration, which can be applied to develop ultra‐compact photonic devices.