Waveguide Device Component (Total 1395399 Papers Found)

We demonstrate 50-Gb/s direct modulation by using 1.3-μm distributed-feedback lasers with a ridge waveguide structure. We employed InGaAlAs material for a multiple-quantum well to obtain a low damping factor <i>K</i>, and fabricated a ridge waveguide structure buried in benzocyclobutene to realize a structure with a low parasitic capacitance. In addition, to obtain high maximum frequency relaxation oscillations fr, we designed the cavity length <i>L</i>), and achie ...
We have developed an organic-inorganic hybrids material having a high thermal stability and low optical loss for telecommunication wavelength. The material is designed to solvent less resin, which is free radical curable with heating 150 °C or UV exposure at room temperature. We have demonstrated to fabricate optical pillar as a method of optical coupling for optical interconnects. Also we have demonstrated to fabricate self-written waveguide and micro lens array. ...
We present the dispersion relations for symmetric planar waveguides in general isotropic media. The planar waveguide structure that utilizes chiral media in the cladding regions is emphasized. Unlike other symmetric planar waveguide configurations in isotropic media, this structure possesses a nondegenerate lowest-order mode. Therefore symmetric planar waveguides using chiral cladding materials can support single-mode operation. ...
A magnetically tunable ferrite-loaded substrate integrated waveguide (SIW) cavity resonator is presented and demonstrated. <i>X</i>-band cavity resonator is operated in the dominant mode and the ferrite slabs are loaded onto the side walls of the cavity where the value of magnetic field is highest. Measured results for single and double ferrite-loaded SIW cavity resonators are presented. Frequency tuning range of more than 6% and 10% for single and double ferrite slabs are obtained. ...
  • Sergiy Steshenko,
  • 2016 9th International Kharkiv Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves (MSMW)
  • 2016
The representations for asymmetrical modes and characteristic equation for the dielectric-loaded circular waveguide are proposed. They have no singularities at the critical points. The proposed representations are convenient for calculation of a plane junction of a dielectric-loaded circular waveguide with another waveguide. ...
  • Abdel Rahman Sallam,
  • 2013 Second International Japan-Egypt Conference on Electronics, Communications and Computers (JEC-ECC)
  • 2013
The goal is to determine spectral dielectric properties ∈ of a dielectric material (sample) machined to fit X-band rectangular waveguide (WG). Two approaches were utilized to achieve this goal, field approach (FA) and circuit approach (CA) in FA the boundary conditions at interfaces of the rectangular sample were used to address the reflection coefficient Γ at the sample input. In CA the ABCD matrices of WG sections (air-sample-air) were cascaded and transformed to obtain system tr ...
We show that integrating waveguides in photonic crystal cavities coupled to quantum dots leads to highly efficient optical nonlinear effects at low photon numbers. Semiconductor quantum dots coupled to photonic crystal cavities provide a platform where large optical nonlinearities can be observed near the single photon level [1,2]. Coupling photonic crystal cavities to a waveguide allows for efficient routing of photons into planar waveguide modes. This architecture can ultimately lead to ultra- ...
A lateral junction type photodiode grown on a semi-insulating InP substrate was realized by 3-step OMVPE growth. The responsivity of 0.27 A/W, 3 dB bandwidth of 6 GHz and 7.5 GHz at a bias voltage of 0 V and −2 V, respectively, were obtained for the stripe width of 1.4 µm and device length of 220µm. An error free transmissions up to 6 Gbps at 0 V were confirmed. ...
For the Low level Radio Frequency system in European XFEL project the real time RF cavity simulator is being built to simulate one RF station. The functional requirements of the project include the simulation of multiple superconducting cavities with various features such as mechanical and fundamental modes, waveguide distribution system and high power system (klystron and amplifiers). The time response of such device for LLRF driving signal must be similar to the real time response of the chain ...
Modern satellite communication systems require high performance filters with great compactness and low mass. These features are traditionally offered by dual mode filters. During the last decades, several designs have been implemented using waveguides with different cross-sections such as rectangular, circular or elliptical, where different coupling structures have been proposed. In this paper, a novel implementation using the equilateral triangular waveguide is introduced. One main advantage of ...
We introduce a new hybrid method for the complete full-wave analysis of stepped horn antennas with waveguides of arbitrary crosssections. The method couples an hybrid Mode Matching (MM)/ Two-dimensional-FiniteElement- Method (FEM2D) for the analysis of the internal part, i.e. for the waveguides step discontinuities from the horn input up to its aperture, to the Generalised- Multipole-Technique (GMT) for the analysis of the horn antennas external part. Since multipoles generates spherical waves, ...
In this study, the thermal-flow characteristics of atmospheric pressure microwave CO2 plasma were numerically investigated by simulation. The electric and gas flow fields in the reaction chamber with a microwave axial injection torch operated at 2.45 GHz were simulated. The microwave launcher had the standard rectangular waveguide WR340 geometry. The simulation was performed by using the COMSOL Multiphysics plasma model with various mass flow rates of CO2. The electric fields, temperature profil ...
Innovative solutions for microwave waveguide filters have recently been developed in order to alleviate the problem of size and weight inherent to waveguide technology. Such solutions yield very compact structures along with highly selective pseudo-elliptic responses. A first class of filters is based on the ridge resonator concept, where a partial-height ridge arbitrarily located and oriented within a waveguide behaves as a quasi-TEM resonator. Depending on the position and shape of the ridge r ...
An improved design is proposed for photonic crystal 90° bend waveguide. 2-Dimensional numerical simulations are carried out for single-line defect in metallic band-gap crystals in square lattice structure. A significant improvement is achieved in terms of transmission and bandwidth over 1 THz with the proposed design. ...
Optical transmission through concentric circular nanoslits is studied in experiments and numerical simulations. Polarized optical microscopic imaging shows that the optical transmission through these apertures is spatially inhomogeneous, exhibiting colored fan texture patterns. Numerical simulations show that these colored fan texture patterns originate from the cylindrical vector polarization of the transmitted beam. Specifically, the transmitted light is in-phase radially polarized at long wav ...
  • É. S. Gevorkyan,
  • 2011 International Conference on Electromagnetics in Advanced Applications
  • 2011
The interaction of two counter-propagating transverse-electric (TE) waves in the absorbing plate, placed in a regular ideal waveguide with arbitrary cross-section, is considered. Supposed, that two coherent waves have different initial phases. The losses of energy of two counter-propagating waves in the plate are calculated. Some features of the physical phenomenon of interference absorption in the absorbing plate in the waveguide are revealed. ...
The ability to construct self-assembled architectures is essential for the exploration of nanoparticle-structured properties. It is one of good strategies by employing molecule-modificated nanoparticles to prepare new materials with particular properties. Herein, we found that captopril (Cap), a biocompatible medicament, could adjust and control the formation of self-assembled gold nanorods (Au-NRs) in high ionic strength solutions. The assembly is in higher-order structures containing both end- ...
The angled-grating broad-area laser is a promising candidate for high power, high brightness diode laser source. The key point in the design is the angled gratings which can simultaneously support the unique snake-like zigzag lasing mode and eliminate the direct Fabry-Perot (FP) feedback. Unlike a conventional laser waveguide mode, the phase front of the zigzag mode periodically changes along the propagation direction. By use of the mirror symmetry of the zigzag mode, we propose and demonstrate ...
The paper presents a theoretical study of a rectilinear quasi-neutral non-relativistic electron beam interaction with semiconductor plasma in a rectangular waveguide placed in longitudinal static magnetic field. It is shown that such an interaction gives rise to broad-band instabilities of space-charge waves and cyclotron waves, propagating along the beam-plasma interface. We also show that the increase in the external magnetic field and the effective frequency of electron collisions in the semi ...
Silica based waveguides on Si fabricated by flame hydrolysis deposition were doped with erbium ions using an aerosol doping technique, and co-doped with GeO2, P2O5 and B2O3. Erbium doping levels in the films were dependent on the nebulized solution concentration and delivery rate of the aerosol to the torch. The erbium solution concentration was varied from 4 to 8 wt%. The refractive index was measured by a prism coupler at 633 nm. FTIR absorption spectra and XRD profiles were made to check the ...
In this paper, we present the design, process and characterization of an AWC bused on a SiGe graded index waveguide plateform, operating at 4.5μm (2180-2280cm<sup>-1</sup>). A transmission of -5dB and a crosstalk below -20dB arc demonstrated. ...
A simple method is presented for describing the sound transmission in a duct containing an array of lined resonators. The impedance of a resonator element is calculated, including the effect of the lining and the duct is modeled as a onedimensional waveguide with lumped impedances. An expression for the TL is derived from considerations of pressure and mass flow continuity along the duct. Experimental data compared to numerical computations show that the method developed here describes satisfact ...
Under injection-locking with downstream amplified spontaneous emission (ASE) carrier spectrally sliced by a 200-GHz arrayed waveguide grating and amplitude-squeezed by a gain-saturated semiconductor optical amplifier (SOA), the injection-level-dependent extinction ratio (ER) and bit-error-rate (BER) penalty of a weak-resonant-cavity Fabry-Perot laser diode (WRC-FPLD) upstream transmitter are investigated. By fixing the downstream power at -13 dBm, the downstream ASE data is amplitude-squeezed by ...
In this paper, Proposes SIW based butterfly shaped slot antenna for 60GHz applications. This frequency is used for wireless communication applications. The proposed antenna is designed by using Rogers substrate with ε<inf>r</inf> =2.2, height is 0.381 mm and the microstrip feed is used with the input impedance of 50ohms. The structure provides 3.05GHz impedance bandwidth in between 57–64 GHz band and matches with VSWR 2:1. The values of Reflection coefficient, Ga ...
This paper proposes a new design concepts for 2-in-1 bandpass filter in millimeter-wave, based on substrate integrated waveguide (SIW) cavities resonators implemented on low temperature co-fired ceramic (LTCC) substrate. Two filters at same center frequency but for different polarizations are integrated and designed using common dual mode cavity resonators in order to reduce the circuit size. Due to the concept of modal orthogonality in the SIW cavities, the filter response could not only be con ...
A numerical analysis of optical waveguides with multilayer dielectric coatings is presented. The simulation is based on the plane wave expansion method, taking into account the exact guided mode profile of the waveguide. The method is free from any assumption about the homogeneity of the waveguide. The power reflectivity is calculated for both antireflection coatings and high-reflection coatings. The accuracy of the model is verified by comparing with the exact results and other simulation metho ...
The design of a THz edge radiation source for the European XFEL is presented.We consider generation of THz radiation from the spent electron beam downstream of the SASE2 undulator in the electron beam dump area. In this way, the THz output must propagate at least for 250 meters through the photon beam tunnel to the experimental hall to reach the SASE2 X-ray hutches. We propose to use an open beam waveguide such as an iris guide as transmission line. In order to efficiently couple radiation into ...
A low-cost and fast real-time PCR system in a pseudo-isothermal manner with disposable capillary tubes based on thermal convection for point-of-care diagnostics is developed and tested. Once stable temperature gradient along the capillary tube has been established, a continuous circulatory flow or thermal convection inside the capillary tube will repeatedly transport PCR reagents through temperature zones associated with the DNA denaturing, annealing, and extension stages of the reaction. To est ...
The wakefield acceleration in a dual grating waveguide slow wave structure (DGWSWS) is proposed. Analytical expression of the wakefield amplitude and frequency is calculated. The wakefield amplitude is analyzed in terms of the grating waveguide parameters, i.e., grating width and grating slot height. The results indicate that the grating wakefield accelerators with shallower slots can operate at terahertz with competitive accelerating gradients when compared with a dielectric wakefield accelerat ...
A millimeter wave antenna is presented for 60 GHz communication using substrate integrated waveguide (SIW) technology along with dialectic resonators (DR). A very thin substrate of RT duroid 5880 having permittivity ε<sub>r</sub>= 2.23, loss tangent tan δ = 0.003 is used. Same material used for the DR having thickness 0.79 mm. H-shape slot in engraved at the top ground plane that acts as a source-radiating aperture. Two pieces of DR are placed on the top metal layer of ...
We report wavelength-division-multiplexing based on lithographically-fabricated slab-waveguide-contained planar holographic Bragg reflectors. Partial diffractive contour writing and contour displacement are successfully demonstrated to enable precise spectral engineering of multiplexer transfer functions and make possible hologram overlay. ...
This letter introduces double layer layouts of open-circuit lines into the electromagnetic bandgap (EBG) structures to enable changing the shunt circuit of the parallel plate waveguide to inductance in compact spaces. That is, compact EBG structures were achieved. The EBG structures, fabricated using standard fabrication processes and using a low-cost substrate (flame retardant type 4), enable a 1-mm-order size for a 2.4-GHz BG. The size is less than 1/10 of the conventional mushroom structures ...
A direct-contact high efficient lens applicator for local microwave hyperthermia treatment of cancer is proposed and developed. The applicator can heat deep and local portion in the dissipative medium such as human body. The dielectric loaded applicators operated at 2450 MHz and 430 MHz show that the heating depth can be reached above twice compared to the simple waveguide applicator which is usually used for hyperthermia. In designing low loss lens applicator, titanium oxide is loaded. The effi ...
We have designed and investigated experimentally a planar periodically corrugated waveguide that allows to control the stop band and hence, transmission through the waveguide. Measurements show that location of the stop band in the frequency spectrum as well as its width depends on the relative position of two corrugated plates. The transmission varies from zero to a maximum value upon shifting of one periodic plate with respect to another on the half period of the corrugation. The results confi ...
We demonstrate the regrowth-free integration of an InP-based arrayed waveguide grating (AWG) with a 1 /spl times/ 8 In/sub 0.53/Ga/sub 0.47/As p-i-n photodiode array. Low-loss polarization-independent adiabatic tapers transfer light from a passive waveguide optimized for external fiber coupling into a higher index waveguide for absorption in the In/sub 0.53/Ga/sub 0.47/As layer. The AWG and individual photodiodes have an external responsivity of 0.46 A/W and a polarization-dependent loss of /spl ...
Abstract. We study an inverse scattering problem for Maxwell’s equations in terminating waveguides, where localized reflectors are to be imaged using a remote array of sensors. The array probes the waveguide with waves and measures the scattered returns. The mathematical formulation of the inverse scattering problem is based on the electromagnetic Lippmann-Schwinger integral equation and an explicit calculation of the Green tensor. The image formation is carried with reverse time migration and ...
We propose and demonstrate a simple and improved absorption geometry using micro-hole architecture for micro concentrating photovoltaic (MCPV). Each micro concentrator is coupled with a very small C-Si solar cell. The incident light is concentrated by micro concentrator on the coupled small area thick film photovoltaic (PV). The PV is designed using proposed micro-hole based architecture to facilitate maximum absorption of the concentrated incident light into the device. Our analysis found that ...
  • ,
  • 2006
This chapter details the measurements of photonic crystal microcavities within silicon membranes. The cavity design is the graded square lattice geometry described in chapter 2 and examined experimentally within InP-based multi-quantum-well membranes in the previous chapter. From a device performance perspective, the primary result of importance in this chapter is the demonstration of a quality factor Q ∼ 40, 000 in a wavelength-scale PC cavity. Of equal importance, however, is the development ...
We present measurements of the femtosecond nonlinear response of fiber waveguide materials, obtained with spectrally resolved two-beam coupling. This simple but sensitive technique provides all the parameters that characterize the third-order nonlinear optical response, including the dynamics. Measurements are made with nanojoule-energy pulses from a mode-locked Ti:sapphire laser and a few millimeters of waveguide preform, without the need for drawing fiber. ...
Based on cascaded sum frequency generation and difference frequency generation, a novel broadband multichannel polarization-insensitive wavelength converter is demonstrated in a periodically poled MgO:LiNbO/sub 3/ (PPMGLN) waveguide and with two pump wavelengths advantageously located out of signal band. ...
Photosensitivity in chalcogenide glass waveguide allows for a permanent refractive index change by means of light exposure [1]. This property can be usefully exploited for post-fabrication trimming of integrated optical devices in order to compensate for fabrication imperfections and alleviate the need for restrictively tight fabrication tolerances [2]. In this work, visible light trimming is exploited to optimize the performance of coupled resonator filters realized by cascading micro-ring reso ...
We study experimentally the propagation dynamics and interaction of spatial optical solitons in a bias-free cell filled with nematic liquid crystals. We reveal and measure long-range effects due to the cell boundaries for a single nematicon as well as for the interacting in-phase and out-of-phase nematicons. We discuss the effect of initial beam focusing and relative input angle on the interaction of in-phase nematicons. © 2009 Optical Society of America OCIS codes: (190.4400) Nonlinear optics, ...
Vane loaded coaxial structures have been found useful for mode rarefaction, when used in oversized, over-moded gyrotron amplifiers. Also such circuits can compensate for the gain reduction which normally occurs while broad-banding of gyro-TWTs. This magnetron like structure was analyzed for its cut-off wave numbers by various techniques. In the present paper the dispersion and interaction impedance characteristics are obtained by boundary matching technique [1]. The results are compared with sim ...
We analyze the existence and stability of nonlinear modes localized at phase-slip waveguide channels and their intersections in two-dimensional photonic lattices with rectangular symmetry. While in linear lattices only one localized mode of this type may exist under special conditions, nonlinearity supports a variety of localized modes including the modes which bifurcate from the symmetric states and describe nonlinear asymmetric localized states. We also study the surface modes localized at the ...
Slot-waveguides allow light to be guided and strongly confined inside a nanometer-scale region of low refractive index. Thus stronger light-analyte interaction can be obtained as compared to that achievable by a conventional waveguide, in which the propagating beam is confined to the high-refractive-index core of the waveguide. In addition, slot-waveguides can be fabricated by employing CMOS compatible materials and technology, enabling miniaturization, integration with electronic, photonic and ...
We study the modes of a symmetric thin-film slab waveguide composed of birefringent crystalline material in the film and in the equivalent substrate and superstrate. In addition we assume that the optical axes of the uniaxial materials of film and substrate are parallel to each other and also parallel (coplanar) to the plane of the film. This simple anisotropic waveguide has interesting properties. It supports only hybrid modes but in the limit of propagation along the optical axis and at right ...