Hybrid plasmonic waveguides for nonlinear applications

In this work, we investigate the use of hybrid plasmonic waveguides (HPWs) for low power all-optical switching via the Kerr effect. An HPW consists of an ultra-thin layer of nonlinear, low-index dielectric sandwiched between metallic and high-index dielectric layers. It combines the deep sub-wavelength optical confinement of gap plasmonic waveguides with the longer propagation lengths of slot waveguides. We model the guided modes of various HPWs using the finite element method, and show that they compare favourably with other nanophotonic waveguides, using an appropriate figure of merit for their nonlinear response in the presence of linear loss. The HPWs are designed to be compatible with existing CMOS or silicon-on-insulator (SOI) technologies, and to permit dense integration of optical switching circuitry.