Simulations of nanometric optical circuits based on surface plasmon polariton gap waveguide

Abstract

Nanometric optical waveguides can be made by using the dependence of surface plasmon polaritons on the gap-width between two parallel metallic plates. This waveguide can be called surface plasmon polariton gap waveguide (SPGW). The H-plane and E-plane optical circuits that consist of SPGWs have been considered. Three-dimensional numerical simulations have been performed for the nanometric optical circuits that consist of straight and branched bend SPGWs. Results show that optical circuits considered in this letter can perform guiding, branching, and bending functions of optical waves in the nanometric device.

Two-dimensionally localized modes of a nanoscale gap plasmon waveguide

“…These plasmons may have especially strong localization in the direction perpendicular to the gap [17][18][19][20][21]. It is also possible to expect that they may experience high transmission through sharp bends, because leakage bend losses into the metal are not possible.…”

“…However, previous attempts to investigate GPWs [17][18][19][20][21] have not resulted in the identification and analysis of dispersion, dissipation, and field structure of specific plasmon modes in gaps of finite dimensions. It is not known if GPWs can support one or more modes, and what are their physical origins.…”

“…Another type of strongly localized plasmons, that may be as interesting, are plasmons in narrow metallic gaps filled completely or partially with dielectric [17][18][19][20][21].…”

Metallic subwavelength-cavity semiconductor nanolasers

“…One of the modes shown in Figure 2a is mostly confined in semiconductor core and the other (Figure 2b) is mostly confined in dielectric layer, which is sometimes termed as plasmonic gap mode. 28,29 In structures with large aspect ratio between Y direction and X direction, the dielectric mode has polarization predominantly along Z direction, while the gap mode is polarized predominantly along X direction. Thus, the two modes resemble TE and TM modes, respectively, propagating along Y direction.…”

“…Part of the mode energy escapes vertically from the InP cladding into the substrate, providing laser emission from the device. Similar waveguides with metal-insulator-metal have been intensively studied both theoretically [26][27][28][29] and experimentally. 30,31 By inserting InP/InGaAs/ InP heterostructure in the middle, our configuration enables compensation for the metal loss by optical gain in the InGaAs layer.…”