The emergence of a dielectric omnidirectional multilayer structure [1]–[4] opens new opportunities for low loss broad-band guiding of light in air. We demonstrate the effectiveness of such an approach by fabricating a broad-band, low-loss hollow waveguide in the 10m region and measuring its transmission around a 90 bend. The generality of the solution enables the application of the method to ma...

For two-dimensional photonic crystals involving infinitely long dielectric rods or air-holes on square or triangular lattices, a number of high performance 60 and 90 waveguide bends are obtained by solving optimization problems involving the radii of a few rods or air-holes as the degrees of freedom. In particular, the proposed 60 bends significantly outperform previous designs that insert thre...

A hybrid optical waveguide having a 90° sharp bend structure, composed of a dielectric straight waveguide, tapered dielectric strip waveguide, and microscale metal gap waveguide, is experimentally demonstrated in an attempt to improve the efficiency of light coupling between dielectric and plasmonic waveguides. Due to both the efficient structure of the taper and metal gap, the calculated coupl...

We apply heterodyne scanning near-field optical microscopy (SNOM) to observe with subwavelength resolution the amplitude and phase of optical fields propagating in several microfabricated waveguide devices operating around the 1.55 microm wavelength. Good agreement between the SNOM measurements and predicted optical mode propagation characteristics in standard ridge waveguides demonstrates the ...

Mid-infrared photonics in silicon needs low-loss integrated waveguides. While monocrystalline germanium waveguides on silicon have been proposed, experimental realization has not been reported. Here we demonstrate a germanium strip waveguide on a silicon substrate. It is designed for single mode transmission of light in transverse magnetic (TM) polarization generated from quantum cascade lasers...

The enormous advancement in science and technology has led to increase in the requirements for high speed data transmission. The increase in the speed of the digital circuits as well as the density of printed circuit board will often result in more challenging signal integrity issues. One of the most important signal integrity issues is radiated emission. We analyzed the radiation in different ...

A numerical study into the physical characteristics of dilute gasparticle flows over a square-sectioned 90◦ bend is reported. Two approaches, namely the Lagrangian particle tracking model and Eulerian two fluid model are employed to predict the gas-particle flows. Renormalization Group based kmodel is used as the turbulent closure for both the approaches; however, for the Eulerian model, additi...