Extreme light confinement and low loss in triangle hybrid plasmonic waveguide

A low-loss triangle hybrid plasmonic waveguide to confine light at an ultra-deep subwavelength scale is proposed and numerically investigated. Compared to other hybrid slot plasmonic waveguides based on cylinder or square semiconductor nanowires, the novel hybrid plasmonic waveguide based on triangle semiconductor nanowire has not only stronger field confinement, but also lower propagation loss. Detailed study of this structure reveals that these advantages originate from the tip enhancement of the triangle semiconductor waveguide. This mechanism of the waveguide permits tolerance for structural imperfection in actual experiments, which is very feasible for experimental realization. The extreme confinement of light can lead to strong electric field around the tip of the triangle semiconductor waveguide, thus can greatly enhance the light-matter interaction. Various applications will benefit from this triangle hybrid plasmonic waveguide, such as the laser, waveguide (cavity) quantum electrodynamics and optomechanics.