Vertical strip metal-insulator-metal waveguide based on a silicon-on-insulator platform

This paper proposes a new ultra-compact strip metal-insulator-metal (MIM) plasmonic waveguide on a silicon-on-insulator (SOI) platform. The waveguide structure can efficiently propagate surface plasmon polaritons (SPPs) within a thin low-index SiO2 layer at an optical wavelength window of 1550 nm. The main parameters of effective refractive index, propagation length, confinement factor, and effective mode area were determined for the proposed waveguide with different waveguide widths. The simulation results were comparable with the in-plane MIM plasmonic waveguide. The proposed layer stack could be monolithically integrated with conventional and hybrid plasmonic SOI-based devices and has the potential of focusing light to nanoscale dimensions.