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We investigate two generic conceptual ideas to obtain bulk 3D negative index metamaterials, which exhibit isotropic properties. One design is a traditional design of 3D wires ended with metallic plates. Another design is based on the nested structures approach, when one element providing magnetic response is inserted into another design with negative dielectric constant. Both constitutive elements...
We present a novel constraint-based routing (CBR) algorithm, which accurately estimates linear and nonlinear physical-layer impairments of 43 and 107 Gb/s channels with duobinary and DQPSK modulation formats by combining fast analytical models for assessing the linear transmission impairments with a split-step Fourier approach optimized for computational speed to estimate the nonlinear intra-channel...
This paper presents a wavelength assignment algorithm for all optical networks. The main idea is to determine the wavelength assignment order for a first fit algorithm taking into account the physical layer effects, such as four wave mixing and residual dispersion, by using a training algorithm inspired in evolutionary computation concepts. The intelligent algorithm uses an external archive to store...
We proposed and demonstrated a novel time domain spectral phase encoding/decoding scheme by time domain stretching and high speed phase modulating short optical pulses. 16 chips, 40 GHz/chip optical codes have been generated and recognized successfully using long chirped fibre Bragg grating (LCFBG) as dispersive components, respectively. Transmission experiments have been carried out successfully...
The polarization anisotropy of microstructure fibre may be introduced especially to provide more possibilities to control the supercontinuum production. Thus polarization degree of freedom should be incorporated to the numerical model. In this paper we analyze numerically the supercontinuum generation in the microstructure fibres with periodically modulated holes ellipticity. Femtosecond pulse propagation...
We experimentally investigate the effect of residual disorder on the dispersion curve of light near a band edge. A Fourier space imaging technique accurately distinguishes the propagating regime from diffusive transport and evanescent regime in planar photonic crystal. We highlight and quantify the impact of the disorder on the group velocity near a band edge. We stress that the achievement and determination...
We have developed specialized arrayed-waveguide gratings for photonic signal processing. The optical pulse synthesizer for an arbitrary optical waveform generation and an optical packet generation, the tunable dispersion compensator, and the optical pulse encoder/decoder are described.
Optical networks are fairly static and operate within well-defined specifications. The addition of new nodes or the upgrade of existing links demands an enormous expenditure. A cost-effective implementation of future optical networks should accommodate old static networks, as well as new highly-efficient networks. It also should be intelligent, self-managed, monitored and dynamically-reconfigurable...
Today Energy Consumption is one of the fundamental topics also for telecommunication networks. In this paper, we report a numerical investigation about energy saving in a transport network both exploiting the transmission properties that permit to reduce 3R equipments and reducing optical links during low traffic periods.
Spectrally efficient duobinary and single-sideband (SSB) intensity-modulated formats are analyzed for the first time to the author's knowledge as downstream signals in wavelength division multiplexing passive optical networks. Back-to-back sensitivity penalty, as well as dispersion, optical signal-to-noise ratio, and dispersion penalties are calculated and compared. Good 2.5 Gb/s remodulation performance...
We are making a study of the out-of-plane losses for the second harmonic generation process in planar two-dimensional photonic crystals made from Al0.3Ga0.7As. We found that for the rhombic symmetry of the lattice it can be obtained a structure in which the out-of-plane losses vanish for both fundamental and second harmonic waves in conditions of very small diffraction for the second harmonic wave...
The propagation and attenuation of electromagnetic waves in the artificial multilayered periodic nanostructures were investigated in the work. We have studied the dispersion of waves in an infinite fine-stratified semiconductor medium. The influence of dissipation on the instability of drift waves in a fine-layered periodic semiconductor structure subjected to an electric field that induces the drift...
We predict self-collimation and superdiffusion of light propagating in materials with periodically modulated gain/loss profile. The modulation is parallel and transverse to the light propagation direction and its periodicity is on the wavelength scale. The self-collimation (or diffraction-free propagation) of the beams is found, which is similar to that observed in photonic crystals. The superdiffusion...
In this paper we investigate the non-linear transmission performance of 40 Gsymbol/s multi-carrier techniques, specifically coherent WDM (CoWDM) for a variety of existing dispersion maps. Whilst the simulations on this paper were performed using NRZ OOK CoWDM implementation, the conclusions are also applicable to other multi-carrier techniques, such as OFDM.
The usage of optical single-sideband signals (OSSB) in 40 Gb/s transmission systems using electrical dispersion compensation (EDC) as a cost-effective alternative to optical dispersion compensation (ODC) is investigated. Optimization of the pseudo-linear regime by adjusting the amount of dispersion compensated at the transmitter and receiver sides is performed using OSSB signals associated with alternative...
The influence of laser chirp on the performance of 40 Gbit/s directly-modulated (DM) long-haul systems (LHS) using optimised optically pre-compensated dispersion maps (OPDM) are assessed through numerical simulation. It is shown that, for a laser chirp parameter of 3.5, the interplay of high laser chirp with linear and nonlinear fiber effects leads to signal distortion that prevents the efficient...
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