We propose a novel broadband coupler for silicon photonics using a hybrid plasmonic waveguide section. The hybrid plasmonic waveguide is used to create an asymmetric section in the middle of a silicon nanowire waveguide coupler to introduce a phase delay to allow for a 3-dB power coupling ratio over a 150 nm bandwidth around 1.55 µm. The device is very compact (<8.5 µm) and has a low insertion ...

A theoretical formulism based on the boundary matching technique has been proposed to study the systematic of an asymmetric waveguide coupler. Same formulism is applicable to a symmetric coupler. The equivalent parallel coupling length to account for the coupling in the two S-shaped regions in the input and the output of the coupler is obtained from the coupler geometry and is dealt with more a...

i Waveguide Coherent Anti-Stokes Raman Spectroscopy (CARS) can be used to measure Raman-active vibrations in thin-layer dielectric waveguides. In waveguide CARS experiments, background-free spectra can be obtained when asymmetric mode combinations are applied. The degree of suppression depends on the waveguide parameters and the wavelengths used. A new method using scanning pump and Stokes beam...

We study light-beam propagation in a nonlinear coupler with an asymmetric double-channel waveguide and derive various analytical forms of optical modes. The results show that the symmetry-preserving modes in a symmetric double-channel waveguide are deformed due to the asymmetry of the two-channel waveguide, yet such a coupler supports the symmetry-breaking modes. The dispersion relations reveal...

We investigate the focusing of surface plasmon polaritons (SPPs) excited with 1.5 microm light in a tapered Au waveguide on a planar dielectric substrate by experiments and simulations. We find that nanofocusing can be obtained when the asymmetric bound mode at the substrate side of the metal film is excited. The propagation and concentration of this mode to the tip is demonstrated. No sign of ...

We report numerical and experimental investigations of asymmetric light propagation in a newly designed photonic structure that is formed by creating a chirped photonic crystal (PC) waveguide. The use of a non-symmetric distribution of unit cells of PC ensures the obtaining of asymmetric light propagation. Properly designing the spatial modulation of a PC waveguide inherently modifies the band ...

We study the nonlinear dispersion and coupling properties of the graphene-bounded dielectric slab waveguide at near-THz/THz frequency range, and then reveal the mechanism of symmetry breaking in nonlinear graphene waveguide. We analyze the influence of field intensity and chemical potential on dispersion relation, and find that the nonlinearity of graphene affects strongly the dispersion relati...

A waveguide optical isolator realized by adhesive bonding of a garnet die, containing a Ce:YIG magneto-optic layer, on a silicon-on-insulator waveguide circuit is demonstrated. The die was bonded on top of an asymmetric Mach-Zehnder interferometer using a 100nm thick DVS-BCB adhesive bonding layer. A static magnetic field applied perpendicular to the light propagation direction results in a non...

An ultra-compact one-dimensional topological photonic crystal (1D-TPC) is designed in a single mode silicon bus-waveguide to generate the Fano resonance lineshape. The comes from interference between discrete boundary state of 1D-TPC and continuum high-order leaky bus-waveguide. Standalone asymmetric lineshapes are obtained experimentally waveguide transmission spectrum with maximum extinction ...

We analyze the existence and stability of nonlinear modes localized at phase-slip waveguide channels and their intersections in two-dimensional photonic lattices with rectangular symmetry. While in linear lattices only one localized mode of this type may exist under special conditions, nonlinearity supports a variety of localized modes including the modes which bifurcate from the symmetric stat...