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This article studies the impact of the fiber link distance when dynamically provisioning connections within a GMPLS-enabled translucent WSON. In particular, two link-cost strategies, namely, uniform and distance-based are compared extending previous works focused on validating a devised OSNR-based IRWA algorithm. In the uniform strategy, the metric for all the links having available wavelengths is...
We report on a new waveguide principle using subwavelength gratings. It is known that diffraction effects are suppressed for waves propagating in materials structured at the subwavelength scale. Subwavelength gratings can create artificial media engineered using microscopic inhomogeneities to enact effective macroscopic behaviour. For the high-index-contrast waveguides, a subwavelength grating can...
This invited paper presents several passive devices containing long silicon photonic wires condensed into spirals. These devices present a large density factor due to their high ratio length over area that improves at the same time their efficiency and fabrication cost. The talk will present the basic equations of the waveguide shape as well as the design and performance of four passive devices under...
The paper proposes to utilize a novel estimation framework in cooperation with monitoring of probe traffic before establishing a lightpath. The scheme strongly decreases the number of lightpath establishment attempts before success.
In this paper, we show how a quantum CNOT-based relational database is built, then we show how to query its quantum tables using the most used SQL-like queries, e.g. INSERT, UPDATE, DELETE and SELECT. We specify each time the evolution of the probability amplitude corresponding to the records before and after the query has been executed and we propose corresponding circuits implementation.
Extensive stochastic numerical simulations are used to revisit and discuss the precise nature of “optical rogue waves” in noise-driven fiber supercontinuum generation (SC). We show that the emergence of solitons with enhanced redshift originates from the collision of two solitons with different frequencies. Our analysis further shows that these solitons do not possess a significantly higher peak power...
A compact green laser diode pumped rare earth laser source is interesting for a range of medical, spectroscopic and communications applications. Since such a device is not commercially available up to now we are working on the development of an erbium-doped fluoride glass up-conversion waveguide laser. The actual fabrication of fluoride glass, especially ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF), strip waveguides...
We present lightwave modulation techniques for high-speed signal generation in digital and analogue applications. Advanced modulation formats, such as differential quadrature phase-shift-keying, amplitude- and phase-shift-keying, quadrature-amplitude-modulation etc, were investigated to obtain enhanced spectral efficiency, where Mach-Zehnder modulators (MZMs) are commonly used to control optical amplitude...
The discrete Fourier Transform (DFT) or its more popular efficient algorithm, the Fast Fourier Transform (FFT) is one of the important mathematical functions in the toolbox of signal processing. To this date its processing speed is limited by the underlying electronic processors. We show that FFT signal processing limitations can be overcome by performing the FFT in the optical domain and demonstrate...
The positive purely imaginary roots of four equations, taking in complex confluent hypergeometric functions, are studied numerically. The first of them involves the Kummer function only, the second is stated through two Kummer and two Tricomi ones, the third is written by two complex Kummer and four real Bessel and Neumann functions, and the fourth - in terms of four Kummer and Tricomi and two Bessel...
The problem of the H-polarized wave scattering by finite chains of circular nanowires is considered. A two-dimensional diffraction problem with rigorous boundary conditions is solved by partial separations of variables method using local polar coordinates of each scatterer. The obtained results demonstrate convergence of the algorithm and good agreement with data known for the conducting and dielectric...
The finite-difference frequency-domain (FDFD) method is a counterpart of the finite-difference time-domain (FDTD) technique in the frequency domain. The FDFD method with the 3D perfectly matched layers appears to be a powerful tool in modeling of nanophotonic cavities, e.g. in extraction of resonance wavelengths (λ) and quality factors (Q) of single or degenerate modes. A single simulation run to...
This talk will focus on the power consumption comparison between point-to-point wavelength division multiplexing (WDM) systems and optical time division multiplexing (OTDM) systems. By keeping the structure simple, the advantages and disadvantages of the WDM and OTDM techniques are highlighted from an energy efficiency point of view. Our analysis shows that in order to be comparable to WDM systems...
In translucent optical networks, the signal will remain in the optical domain as long as possible and will be regenerated only when its quality falls below a threshold or a wavelength contention has to be resolved. In these networks a limited number of regenerators are placed at a selected set of nodes. As OEO regenerators are expensive, the problem of regenerator site selection is of paramount importance...
We consider the lasing modes in a spiral active microcavity as solutions to the 2-D linear eigenproblem for the Maxwell equations with exact boundary and radiation conditions. This problem is reduced to the set of two coupled boundary integral equations with smooth and integrable kernels discretized using the adequate quadrature formulas. Then eigenvalues are found numerically with guaranteed accuracy...
Optimization of NALM parameters for phase-preserving amplitude regeneration of a multilevel star8-QAM signal was performed in numerical simulations. A Q-factor improvement of 5 dB for each amplitude level was shown. Possibilities of performance improvement using a power-dependent nonlinear phase shift and a nonlinear amplifier gain were investigated. A Q-factor improvement up to 11 dB for each level...
Metamaterials (MTMs) claim a lot of attention worldwide. Description of the MTMs in terms of effective parameters is a simple and useful tool for characterisation of their electromagnetic properties. So a reliable effective parameters restoration method is on demand. In this paper we report about our activity and advances in the effective properties of metamaterials characterization. We present here...
The tunability of Pr3+/Yb3+ doped ZBLAN fiber lasers has been investigated. A broad tuning range of 17 nm with narrow linewidth was obtained for red and orange wavelengths. The fiber lasers were pumped with pigtailed laser diodes at 845 nm. No free space optics except of the tuning block was used.
In this work, we report for the first time the experimental achievement of an all-fibered polarization attraction, which can occur in optical fibers at telecommunication wavelengths. More precisely, we have experimentally shown that is possible to all-optically control and stabilize the state of polarization of a 10 Gbit/s telecommunication signal through the injection of a counter-propagating control...
This brief review has concentrated on recent research to which the author has been directly connected. It ranges over several domains under the general heading of micro-/nano-photonics and these domains may be labelled as metamaterials, photonic (quasi-)crystals and photonic wire structures. Several different metals are featured, while the words 'silicon photonics' are appropriate for much but not...
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