A Long Propagation Distance Hybrid Triangular Prism Waveguide for Ultradeep Subwavelength Confinement

A novel hybrid triangular prism waveguide is implemented in this paper, which consists of a silicon triangular prism nanowire loaded above a metallic triangular prism with a low index dielectric gap between them. The enhanced field confinement and long propagation length can be realized by strong hybridization coupling between dielectric modes and plasmon polaritons. A normalized effective mode area (0.005-0.03), along with an extremely long propagation distance (96-304 μm), has been achieved at a telecommunication wavelength of 1.55 μm. In addition, the effects of actual machining errors on the mode properties of hybrid triangular prism waveguide indicate that the properties of the fundamental mode are quite robust against possible manufacture imperfections. The excellent optical properties make such waveguide a promising component of ultracompact silicon-based integrated photonic devices.