Hybrid dual wedge plasmonic waveguide with long-range propagation and subwavelength mode confinement

A hybrid dual wedge plasmonic (HDWP) waveguide consisting of two dielectric wedges and a diamond metal wire was proposed. The coupling between dielectric wedge waveguide mode and long-rang surface plasmon polariton mode results in both low propagation loss and ultra-deep-subwavelength confinement. The HDWP waveguide achieves a normalized mode area of 2.9 x 10(-3) with a moderate propagation length of 532 mu m or a propagation length of 3028 mu m with a normalized mode area of 6.2 x 10(-3). The impacts of possible fabrication imperfections on the mode properties are studied. The results indicate that the HDWP waveguide is quite tolerant to fabrication errors.