A broadband, multichannel, single-mode, planar waveguide based spectrometer was developed for probing molecular monolayers. A protein sub-monolayer (thickness h @ 3 nm, imaginary part of refractive index kl oe 0.01) immobilized on the waveguide surface was characterized by the waveguide attenuated total reflection (ATR) spectrometer. A sensitivity enhancement of 4 orders of magnitude, compared ...

In this work, we theoretically and experimentally demonstrate a highly sensitive porous silicon membrane waveguide biosensor in the Kretschmann configuration, and show how the cladding material directly impacts the waveguide sensor detection sensitivity and resonance width. Dielectric and metal-clad porous waveguides in the Kretchmann configuration have the potential to achieve significantly en...

Incorporation of planar waveguide technology into a spectroelectrochemical sensor is described. In this sensor design, a potassium ion-exchanged BK7 glass waveguide was over-coated with a thin film of indium tin oxide (ITO) that served as an optically transparent electrode. A chemically selective film was spin-coated on top of the ITO film. The sensor supported five optical modes at 442 nm and ...

We report performance characteristics of a thulium doped ZBLAN waveguide laser that supports the largest fundamental modes reported in a rare-earth doped planar waveguide laser (to the best of our knowledge). The high mode quality of waveguides up to 45 um diameter (~1075 μm(2) mode-field area) is validated by a measured beam quality of M(2)~1.1 ± 0.1. Benefits of these large mode-areas are dem...

High-gain and low-profile antennas are required for high-speed wireless communication systems and mechanically-scanning automotive radars in the millimeter-wave band. Waveguide antenna is one of the most attractive planar antennas for such millimeter-wave systems because of its low loss and high efficiency characteristics in high frequency band. Travelling-wave excitation is more effective for ...

Using selective area epitaxy to produce three-dimensional GaN structures, two different concepts for laser diodes (LDs) with semipolar quantum wells (QWs) are developed, each having distinct advantages and disadvantages. The first approach utilizes a stripe with triangular cross-section not only to grow semipolar quantum wells on, but also as waveguide and resonator cavity. Based on simulations...

Time-harmonic acoustic waves in an ocean of finite height are modeled by the Helmholtz equation inside a layer with suitable boundary conditions. Scattering in this geometry features phenomena unknown in free space: resonances might occur at special frequencies and wave fields consist of partly evanescent modes. Inverse scattering in waveguides hence needs to cope with energy loss and limited a...

Despite the difficulty in fabrication, resonant tunneling diodes ~RTD! have found a great deal of usage in the analog, digital, and mixed signal realms as a means of increasing the speed of signal processing circuitry or in reducing the static power dissipation in the circuitry. Nevertheless, RTDs suffer from their nonplanar structure. In this paper, we present a planar diode which operates via...

In this paper, a metal-clad planar optical waveguide biosensor with five layer structure is studied theoretically for the detection of Pseudomonas and Pseudomonas-like bacteria. Using a very simple boundary matching technique, we derive the mode equation and other necessary formulae for the proposed biosensor and analyse its performance under different conditions related to its constituents. Th...

Abstract. We analyse theoretically for the first time to our knowledge the perfect phase matching of guided TE and TM modes with a multilayer waveguide composed of linear isotropic dielectric materials. Alongside strict investigation into dispersion relations for multilayer systems, we give an explicit qualitative explanation for the phenomenon of mode matching on the basis of the standard one-...