Analytical Study of phase-matched modes of diffused, proton-exchanged LiNbO3 waveguides

In this paper, we present an analytical model for guided modes determination in diffused proton-exchanged LiNbO(3) waveguides. The dispersion equation and guided mode shapes are obtained. These results calculated at different wavelengths permit for the phase matching exploration in phenomena such as second harmonic generation

Novel Ultra-Wideband Bow-Tie Antenna with High Front-to-Back Ratio and Directivity

We present a novel directional ultra-wideband antenna based on the bow-tie geometry. The proposed design, unlike the conventional bow-tie radiator, has an inherently different radiation mechanism, which relies on magnetic currents excited in properly designed slots. This in turn allows to maintain good antenna performance even when a planar reflector is placed below the antenna that gives rise to high front-to-back ratio and directivity over a band extending from 4.8 to 6.1 GHz

A COMPACT MONOPOLE MIMO ARRAY FOR THE 5\u20136-GHz BAND

In this article, a low-cost compact multiple-input multiple-output array composed of three coplanar waveguide-fed monopoles printed on flame retardant 4 substrate is presented. The particular feeding mechanism of each single element allows for a wideband behavior, and the specific delta (D) shape arrangement of the three radiators leads to a remarkably small footprint. The proposed design is capable of operating in the entire 5\u20136-GHz spectrum hence resulting particularly attractive for the IEEE 802.11n 5-GHz standard. A prototype was fabricated and connected to a Ralink 3 3 evaluation board to assess the throughput performance in a typical indoor scenario. The effectiveness of the proposed array is confirmed by experimental result

Time domain bidirectional beam propagation method for second harmonic generation in multilayers

We propose a time domain bidirectional beam propagation method based on scattering operators for wide band pulse propagation in nonlinear multilayers. The reported numerical examples demonstrate the applicability of the algorithm for the analysis of temporal effects related to the process of second harmonic generation

Nonlinear bidirectional beam propagation method based on scattering operators for periodic microstructured waveguides

Beginning with a recently proposed bidirectional beam propagation method based on scattering operators, we develop an accurate and efficient method for the analysis of periodic microstructured waveguides in a nonlinear regime. This novel numerical tool allows us to describe the role played by losses that are due to diffraction and the effects of the finite size of the beams in nonlinear optical devices with strong lateral confinement of the optical intensity. We demonstrate the effectiveness and the efficiency of our method with numerical examples

Time Domain BPM for Ultrashort Pulse Propagation in Nonlinear Multilayers

We elaborated a time-domain bidirectional beam propagation method able to efficiently model ultrashort pulse propagation in quadratic multilayered devices. This novel numerical tool permits us to identify the reasons that determine the reduction of second-harmonic generation efficiency as the pump pulses duration decreases