We performed numerical analysis and design parameter optimization of a silicon-based grating waveguide refractive index (RI) sensor. The performance of the grating waveguide RI sensor was determined by the full-width at half-maximum (FWHM) and the shift in the resonance wavelength in the transmission spectrum. The transmission extinction, a major figure-of-merit of an RI sensor that reflects bo...

In this paper, we investigate a real-world problem, constructing optical waveguide structures using evolutionary search strategies. Optical waveguide is the most basic component in optical communication and integrated optical circuits. The structure of a waveguide is of great importance as it would significantly impact on the quality of light transmission. The aim of this paper is to find a set...

We theoretically investigate three-dimensional plasmonic waveguide-cavity structures, built by side-coupling stub resonators that consist of plasmonic coaxial waveguides of finite length, to a plasmonic coaxial waveguide. The resonators are terminated either in a short or an open circuit. We show that the properties of these waveguide-cavity systems can be accurately described using a single-mo...

Matching circuits for waveguide-nanoantenna connections are difficult to implement. However, if the waveguide permits only one-way propagation, the matching issue disappears since back-reflections cannot take place; the feed signal is converted to radiation at high efficiency. Hence, a terminated one-way waveguide may serve as an assembly consisting of a waveguide, a matching mechanism, and an ...

A rectangular waveguide band-stop filter using electromagnetic crystals (EMXT) surface as the top and bottom walls is presented in this letter. The EMXT surface has a band gap that can prevent electromagnetic wave from propagating along the waveguide. Dispersion properties of the waveguide filter are analyzed using an approximated lumped-element circuit model. A W-band prototype based on the pr...

We propose a new stratified waveguide grating coupler (SWGC) to couple light from a fiber at normal incidence into a planar waveguide. SWGCs are designed to operate in the strong coupling regime without intermediate optics between the fiber and the waveguide. Two-dimensional finite-difference time-domain simulation in conjunction with microgenetic algorithm optimization shows that approximately...

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 demonstrate the generation of light in an optical waveguide strongly coupled to a periodic array of metallic nanoantennas. This coupling gives rise to hybrid waveguide-plasmon polaritons (WPPs), which undergo a transmutation from plasmon to waveguide mode and vice versa as the eigenfrequency detuning of the bare states transits through zero. Near zero detuning, the structure is nearly transp...

Silicon photonics is merging as a unified platform for driving photonic based telecommunications and for local photonic based interconnect but it suffers from large footprint as compared with the nanoelectronics. Plasmonics is an attractive alternative for nanophotonics. In this work, two CMOS compatible plasmonic waveguide platforms are compared. One is the horizontal metalinsulator-Si-insulat...