Propagation characteristics of the supermode based on two coupled semi-infinite rib plasmonic waveguides

Abstract

We report on the propagation characteristics of a plasmonic waveguide structure based on two coupled rectangular wedges. Dispersion, propagation loss, and field distributions are investigated by three-dimensional finite-difference time-domain method. The considered structure supports only one supermode over 30THz bandwidth, and the calculated propagation loss at lambda=1.55mum is 0.0257dB/mum, which is lower than the existing report by 1.7 times while keeping comparable field localizations. The all-planar structure in conjunction with the linearly dispersive characteristic over a wide operational bandwidth signifies its great potential for optical signal transporting in nanophotonic circuits.

Design and Analysis of an Ultra-Compact and Ultra-Wideband Polarization Beam Splitter Based on Coupled Plasmonic Waveguide Arrays

“…These structural parameters place a stringent fabrication tolerance and may produce excess loss due to not perpendicular or the roughness of the sidewalls. In recent years, plasmonic waveguides [10]- [12] have been extensively investigated aiming at the realization of nanophotonics and ultra-compact PLCs. Surface plasmon polaritons (SPPs) [13], being tightly confined at the metal-dielectric interface, also provides useful properties such as all-angle refraction [14] and polarization selectivity.…”

“…Surface plasmon polaritons (SPPs) [13], being tightly confined at the metal-dielectric interface, also provides useful properties such as all-angle refraction [14] and polarization selectivity. Low-loss propagation [11], [12], high degree of field confinement, and insensitivity to structural imperfections [15] render plasmonic waveguide a potential building-block for the construction of ultra-compact devices. In this letter, we describe the design of an ultra-compact wideband operational PBS based on coupled plasmonic waveguide arrays.…”

Design and Characterization of Dielectric-Loaded Plasmonic Directional Couplers

“…As the coupling length shows an exponential dependence on , so does , and by fitting the EIM results of , the analytical expression (5) can be established, with and being the wavelength dependent factors. Using this and the expression for the waveguide separation throughout the S-bend given by (1), the phase change due to an S-bend can be written as (6) Solving this equation, using the S-bend parameters m and m (used in the fabricated DC samples) confirm that the coupling increases with wavelength, but decreases exponentially with (Fig. 2), as was the case in the parallel section.…”

“…Due to the metal involved, another challenge in the design is to minimize the propagation losses when retaining the demand of single-mode propagation and strong confinement. Several different plasmonic waveguide structures seeking to obey these demands have been proposed and investigated in recent years, among which are V-shaped and rectangular grooves in an otherwise smooth metal film [4]- [6], thin metal stripes embedded in a dielectric [7], [8], and chains of closely spaced metal nanoparticles [9], [10]. The possibility of realizing wavelength-dependent components and, in particular, directional coupling with these types of plasmonic waveguides has been also investigated recently by several research groups [11]- [19].…”

Analytic Modeling of Trench Waveguides for Channel Plasmon-Polariton Using Full-Hybrid Trial-Field Functions

“…Another method, the semianalytic method of lines, has proved to be a very useful tool for numerical modeling of plasmonic waveguides [13][14][15][16]. Minh and others [17] recently have applied MoL to calculate the propagation characteristics of trench-CPP waveguides and have compared their results with those obtained by EIM [12] and FDTD [18]. The present authors have carried out a simple analytic modeling of trench-CPP guides using full-hybrid trial-field functions.…”