We present comparative measurements of two Mach–Zehnder interferometers, one with Y-junction couplers and the other with MMI couplers, both developed in siliconon-insulator technology and using plasma dispersion effect for light phase modulation. Measurements of fiber-to-fiber losses, absorption coefficient, output intensity vs. time and extinction ratio vs. frequency have been performed at λ= ...

We present simple and accurate relations for the study of parallel and curved tunable single-mode fiber directional couplers employing step-index or graded-index fibers. Analytical results for the various coupler parameters such as coupling coefficient, effective interaction length, tunability, and channel wavelength separation in directional coupler wavelength filters are presented. These resu...

Articles you may be interested in Vertically integrated metal-clad/silicon dioxide-shell microtube arrays for high-spatial-resolution light stimuli in saline Appl. On-chip intra-and inter-layer grating couplers for three-dimensional integration of silicon photonics Appl. Monolithically integrated low-loss silicon photonic wires and three-dimensional tapered couplers fabricated by self-profile t...

Variable power splitting ratio 2x2 MMI couplers using multimode waveguide holograms are analyzed. Theoretical analysis shows that variable splitting ratios can be obtained with surface relief holograms on MMI couplers with fixed dimensions. Devices with paired-imaging lengths are designed on a silicon-on-insulator (SOI) platform. Beam propagation simulations are used to verify a matrix theory a...

Several types of silicon fluidic coupler have been designed, fabricated, and tested to facilitate external connections to MEMS (microelectromechanical systems) fluidic devices. By using both bulk micromachining and DRIE (deep reactive ion-etching) techniques, couplers of different geometry have been produced for use with any standard MEMS fluidic port. In addition, couplers are easily modified ...

Circular integrated optical (ring or disk) microresonators are increasingly employed as compact and versatile wavelength filters. In this paper, we investigate a two dimensional frequency domain model for these devices, based on spatial coupled mode theory. The microresonators are functionally represented in terms of two couplers with appropriate connections using bent and straight waveguides. ...

resonator model For modeling purposes, the MR is decomposed into two bent-straight waveguide couplers, represented by the blocks (I) and (II), which are connected to each other by two segments of the cavity. The external connections are provided by straight waveguides. Here we consider only forward propagating modes of uniform polarization. We assume that all elements are linear and that the ba...

We report rigorous approach for the design of differential coupled-line directional couplers in multilayer dielectric structures. In the proposed procedure numerically calculated per-unit-length parameters of coupled transmission lines are utilized for derivation of differential couplers' properties. The known description technique with multimode scattering parameters has been extended to the e...

Chemoreceptor arrays are supramolecular transmembrane machines of unknown structure that allow bacteria to sense their surroundings and respond by chemotaxis. We have combined X-ray crystallography of purified proteins with electron cryotomography of native arrays inside cells to reveal the arrangement of the component transmembrane receptors, histidine kinases (CheA) and CheW coupling proteins...

We report a subwavelength grating (SWG) coupler for coupling light efficiently into in-plane semiconductor nanomembrane photonic devices for the first time. The SWG coupler consists of a periodic array of rectangular trenches fabricated on a silicon nanomembrane (SiNM) transferred onto a glass substrate. At a wavelength of 1555.56 nm, the coupling efficiency of the fabricated 10 µm wide, 17.1 µ...