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A Multiwavelength BEFL with virtual mirror concept is demonstrated with an additional pump power to provide higher gain. 616 mW provided by a 975 nm pump is added to the conventional of 130 mW1480 nm pump. Wide tuning range of 39 nm wavelengths was achieved and maximum of 9 laser lines was observed from the proposed design.
Junction temperature and thermal resistance are important factors in determining the overall performance of LED packages. Thermal transient measurements of multi-chip high brightness LED package with two specified positions under various ambient temperatures are discussed in this paper. Case 1 and case 2 are introduced as the inclined angle of the package at 0° and 90°. The main goal is to study the...
An L-band erbium doped fiber amplifier (EDFA) with dual-stage architecture was proposed that gives a considerably flatten wavelength response of less than 3 dB gain variations. Gain of 25 dB was achieved throughout the L-band region (1570 nm – 1605 nm) and noise figure of less than 4.5 dB was obtained when the pump power was distributed equally to two different stages with different length of erbium-doped...
This study investigates the capability of an ultrashort pulse laser in a ring cavity of erbium-doped fiber laser (EDFL). Generation of pulses was performed by inserting a carbon-nanotube saturable absorber in this EDFL. Mode-locked laser was achieved with an average power of 20mW and a peak power of 3.37kW. Pulse duration laser of 950fs with repetition rate of 6.24MHz was obtained at 3dB bandwidth...
Code pulses of spectral amplitude coding (SAC)-optical code division multiple-access (OCDMA) are overlaid onto a multichannel wavelength division multiplexing (WDM) system. Modified quadratic congruence (MQC) codes are developed as the signature codes for the SAC/OCDMA system to avoid the overlapping between signals of both systems. In addition, simultaneous transmission of both optical CDMA users...
The modal characteristics of a step-index waveguide with a hyperbolic core-cladding boundary have been studied. For the study of this new waveguide we select an elliptical coordinate system ,so that cross-sectional boundary is represented by a hyperbola .Using suitable boundary condition, and the field components,determined for a fourth order determinantal characteristic equation is obtained. The...
The impact of Chromatic Dispersion (CD) and Non-Linear Effects (NLE) including Self-Phase Modulation (SPM) and Four-Wave Mixing (FWM), on the performance of a Variable-Weight Optical Code Division Multiple Access (VW-OCDMA) system at 1.25 Gbps is analyzed by simulation. The results show that CD is the most dominant effect, which increases the users bit error rate (BER) especially for the users with...
In this paper, we have evaluated the performance of spectral amplitude coding optical code-division multiple-access (SAC-OCDMA) systems. A performance comparison has been made between various OCDMA signature sequences (random diagonal (RD), modified double weight (MDW), and modified quadratic congruence (MQC) codes). Analytical expressions have been used to analyze the bit-error rate (BER) value for...
In this paper, the implementation of subcarrier multiplexing technique in spectral amplitude coding (SAC) optical code division multiple access (OCDMA) network using Zero Cross Correlation code is developed and investigated. Theoretical analysis is done to determine the signal-to-noise ratio of such network and analysis of the performances in term of bit error rates are presented. Simulations are...
We report about new polymer optical microresonators (OM) optical filters designed for operating wavelengths 1550 nm and filtering out wavelength 1490 nm. The first step was to design a single mode polymer waveguide by using BeamPROP™ software and after that a microring resonators were designed by Finite-Difference Time-Domain method using FullWAVE™ software. We also did modelling of three types of...
A multi-wavelength Brillouin fiber laser (BFL) with 200nm (1430 nm to 1630 nm) wavelength tuning is presented. The BFL configuration comprises of a long 25-km SMF-28 to provide non-linear gain and optical circulator to re-inject higher order Stokes signal into cavity to seed a cascaded BFL lines. The proposed configuration produced up to 17 Brillouin Stoke lines with channel spacing of 11GHz in 1510...
A new code family for Spectral Amplitude Coding Optical Code Division Multiple Assess (SAC-OCDMA) system has been proposed in this paper. The new code family we call it Dynamic Cyclic Shift (DCS) code. The DCS code has many advantages. However, the DCS code can be generated without code parameter limitation. In addition, the shorter code length and variable cross correlation (λc ≤ 1) of the DCS code...
The energy levels of organic semiconductor materials; poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM), were investigated using photo-electron spectroscopy in air (PESA) and UV-Vis spectrophotometer. Solution-processed organic thin-film transistors (OTFTs) based on P3HT/PCBM blend thin film in a top source-drain contact structure was fabricated, and the optical response...
We investigate the performance of GaInNAs broad area laser diode at room temperature when the InGaAs and GaNAs barrier configuration is applied to the quantum well system in the active region. The simulation software PICS3D is used in this work. By plotting the light versus the current curve, we can extract the differential quantum efficiency, ηd and internal quantum efficiency, ηi for the laser....
The paper is devoted to the investigation of dynamics of system, consisting of interacting two-level atoms and field (cavity field). To such system covers also Jaynes-Cummings model. In this paper, evolution of two-level many bosons system interacting with a field is investigated by means of generalized kinetic equation. On base of the Bogolyubov's method (method of elimination of bosons), solution...
The paper presents design, modeling, fabrication and analysis of integrated diffractive optical elements (DOEs) for optical sensor applications. The sensors presented depend on two major mechanisms: Surface Plasmon Resonance (SPR) and Guided Mode Resonance (GMR). In SPR-based sensor, DOEs are implemented on the backside of the sensor chip for an in/out coupler at large angle of operation. The proposed...
We report the improvement and noise analysis of correlated photon-pair generation in an ultra-compact 96 µm long dispersion-engineered silicon slow-light photonic crystal waveguide pumped by picosecond pulses. The key metrics for a photon-pair source: coincidence to accidental ratio (CAR) and pair brightness were measured to be a maximum 27 at a pair generation rate of 0.002 pair per pulse. We performed...
Microfibers and its knot resonator structure are fabricated using a flame-brushing technique for current sensor and tunable Erbium-doped fiber laser (EDFL) applications. A compact current sensor using a microfiber knot resonator (MKR) is demonstrated based on idea of measuring the thermally induced resonant wavelength shift as a result of heat produced due to the flow of electric current over a copper...
The paper presents some theoretical background and results obtained for 3×3 incoherent MIMO system operating over 4.4 km of SO Jim core silica GI MM fiber Although 3×3 incoherent MIMO transmission was possible the quality of the received channels varied between channels and in time.
Inside any wave-guiding structure, such as optical fibers, light propagates in a discrete set of modes. Each mode is defined by its direction of propagation, amplitude profile, phase distribution and polarization. Proper modal excitation and manipulation can yield to novel and low cost optical devices. This paper covers the concepts of designing low cost and functional optical fiber devices based...
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