31 research outputs found
Circulating spatial solitons
A class of optical spatial solitons exhibiting propagation in a closed-loop orbit in a two-dimensional plane is presented. A closed-form particlelike model is derived, indicating that the quasi-centrifugal force acting on these solitons can be balanced by an inhomogeneity in the nonlinear index of refraction. Specifically, a circular-shaped nonlinear interface is shown to facilitate stable orbital propagation of solitons that carve their own circular cavity for a wide range of nonlinearity parameters
Programming of inhomogeneous resonant guided wave networks
Photonic functions are programmed by designing the interference of local waves in inhomogeneous resonant guided wave networks composed of power-splitting elements arranged at the nodes of a nonuniform waveguide network. Using a compact, yet comprehensive, scattering matrix representation of the network, the desired photonic function is designed by fitting structural parameters according to an optimization procedure. This design scheme is demonstrated for plasmonic dichroic and trichroic routers in the infrared frequency range
Nano plasmon polariton modes of a wedge cross section metal waveguide
Optical plasmon-polariton modes confined in both transverse dimensions to
significantly less than a wavelength are exhibited in open waveguides
structured as sharp metal wedges. The analysis reveals two distinctive modes
corresponding to a localized mode on the wedge point and surface mode
propagation on the abruptly bent interface. These predictions are accompanied
by unique field distributions and dispersion characteristics.Comment: 6 pages, 5 figure
Ultrasmall volume Plasmons - yet with complete retardation effects
Nano particle-plasmons are attributed to quasi-static oscillation with no
wave propagation due to their subwavelength size. However, when located within
a band-gap medium (even in air if the particle is small enough), the particle
interfaces are acting as wave-mirrors, incurring small negative retardation.
The latter when compensated by a respective (short) propagation within the
particle substantiates a full-fledged resonator based on constructive
interference. This unusual wave interference in the deep subwavelength regime
(modal-volume<0.001lambda^3) significantly enhances the Q-factor, e.g. 50
compared to the quasi-static limit of 5.5.Comment: 16 pages, 6 figure
Efficient Coupling between Dielectric-Loaded Plasmonic and Silicon Photonic Waveguides
The realization of practical on-chip plasmonic devices will require efficient coupling of light into and out of surface plasmon waveguides over short length scales. In this letter, we report on low insertion loss for polymer-on-gold dielectric-loaded plasmonic waveguides end-coupled to silicon-on-insulator waveguides with a coupling efficiency of 79 ± 2% per transition at telecommunication wavelengths. Propagation loss is determined independently of insertion loss by measuring the transmission through plasmonic waveguides of varying length, and we find a characteristic surface-plasmon propagation length of 51 ± 4 μm at a free-space wavelength of λ = 1550 nm. We also demonstrate efficient coupling to whispering-gallery modes in plasmonic ring resonators with an average bending-loss-limited quality factor of 180 ± 8
Dielectric based resonant guided wave networks
Resonant guided wave networks (RGWNs) are demonstrated to operate based on dielectric waveguides, broadening the scope of this optical design approach beyond plasmonics. The intersection of two dielectric waveguides that is modified by a tuned scattering particle is shown to function as an equal power splitting element, a key enabler of resonant guided wave networks. We describe structures composed of two types of waveguides, Si slabs and SOI ribs, at the telecom frequencies using both, Au and etch, based scatterers
Resonant guided wave networks
A resonant guided wave network (RGWN) is an approach to optical materials
design in which power propagation in guided wave circuits enables material
dispersion. The RGWN design, which consists of power-splitting elements
arranged at the nodes of a waveguide network, results in wave dispersion which
depends on network layout due to localized resonances at several length scales
in the network. These structures exhibit both localized resonances with Q ~ 80
at 1550 nm wavelength as well as photonic bands and band-gaps in large periodic
networks at infrared wavelengths.Comment: 9 pages, 5 figure