Excitation of surface plasmons in graphene-coated nanowire arrays

One of the important challenges that graphene must overcome before it can legitimately declare its irreplaceable position among the fields of plasmonic materials is to achieve efficiently coupling to external light. In this paper, we demonstrate an effective solution to this problem by exciting localized surface plasmon polaritons (SPPs) on graphene-coated nanowire arrays (GCNAs). These SPPs are analyzed by introducing a universal scaling law that considerably simplifies the understanding of these modes. Meanwhile, numerical experiments are carried out to demonstrate the theoretical analysis of plasmon excitations. The excited SPPs permit the control through both geometrical and physical properties. The proposed structure can be used as a tunable optical filter, a highly sensitive refractive index sensor, and other plasmonic modulation devices. Published by AIP Publishing.