We demonstrate that nonlinear directional coupler with special bending of waveguide axes can be used for all-optical switching of polychromatic light with very broad spectrum covering all visible region. The bandwidth of suggested device is enhanced five times compared to conventional couplers. Our results suggest novel opportunities for creation of all-optical logical gates and switches for po...

We design a high dynamic range electric field sensor based on domain inverted electro-optic (E-O) polymer Y-fed directional coupler for electromagnetic wave detection. This electrode-less, all optical, wideband electrical field sensor is fabricated using standard processing for E-O polymer photonic devices. Experimental results demonstrate effective detection of electric field from 16.7V/m to 7...

The paper proposes and investigates the topology of a phase shifter based on directional coupler. dimensions such device are reduced by using artificial transmission lines instead quarter-wave sections. By connecting several pairs phase-shifting cells usual one, it was possible to obtain design with two shifts (instead one).

The fiber loop mirror based on a ring configuration is one of the devices in optical fibers most used in communications and sensors (Mortimore, 1988). The device is formed when the two output ports of a directional coupler are spliced. In this configuration, the two waves at the coupler outputs travel in opposite directions but following the same optical paths in an optical fiber ring, which as...

Introduction: With the increasing variety of commercial wireless applications, there is now a requirement to incorporate several transceivers into a single hardware device [1]. To achieve high integration and minimise costs, it is an advantage to design transceivers that can be reconfigured for different frequency bands or share common blocks, rather than implementing the transceivers separatel...

In this paper a novel all-optical logic NAND, NOR and XOR gate based on nonlinear directional coupler theory is demonstrated. We use the identical structure which contains three waveguides, for designing these gates; the only difference however, is the power of inputs light beam. In other words, while a beam with 4 W/μm in power considered as logical one, the output is NAND gate and if a beam w...

In this paper a novel all-optical logic NAND, NOR and XOR gate based on nonlinear directional coupler theory is demonstrated. We use the identical structure which contains three waveguides, for designing these gates; the only difference however, is the power of inputs light beam. In other words, while a beam with 4 W/μm in power considered as logical one, the output is NAND gate and if a beam w...

31.1 Silicon Photonics Fundamentals 31.1.1 A historical perspective 30.1.2 Silicon waveguide 30.2 Coupling Light to Silicon Waveguides 30.2.1 Problem of external coupling 30.2.2 Nonvertical taper (NVT) 30.2.3 Grating coupler 30.2.4 Nanotaper 30.3 Resonant Structures 30.3.1 Principle of directional coupling 30.3.2 Mach-Zehnder interferometers 30.3.3 Ring Resonators 30.4 Modulation of Optical Sig...

The design of grating-assisted, channel waveguide, codirectional couplers is demonstrated using the Gel’fand-Levitan-Marchenko inverse scattering method. Weighted coupling coefficients are computed from rational function expressions for the desired wavelength response. Approximate formulas are derived which relate the waveguide and grating geometries to the computed coupling coefficients. The t...

We study, theoretically and experimentally, the evolution of optical waves with randomly-fluctuating phases in a spatially chirped nonlinear directional coupler. As the system crosses its linear resonance, we observe collective self-phase-locking (autoresonance) of all mutually-incoherent waves, each with its own pump, and simultaneous amplification until the pumps are exhausted. We show that t...