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In this work I present a new semi-vectorial model for analysis of photonic-crystal VCSELs (PC-VCSELs), which is a combination of the plane-wave expansion method with the effective index approximation. It allows to consider vectorial properties of electromagnetic field in three-dimensional structures while being still much more numerically efficient than fully-vectorial methods. I show the simulation...
Wavelength division multiplexing systems use multiplexers and demultiplexers to increase network capacity by allowing several information channels to be placed into one fiber. Depending on the application multiplexers and demultiplexers can have wide, coarse or dense channel spacing as well as different number of channels that they process. There are many techniques available today for realization...
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.
Experimental 2D solitonic coherent interactions between two parallel beams in photorefractive iron doped indium phosphide (InP:Fe) will be presented. These measurements will be discussed taking into account the dependency on the relative distance between the beams, the light intensity and the temperature. This methodology is very attractive as regards both the employed wavelengths and the possibility...
We proposed the implementation of the all-optical signal denoising and Mexican hat mother wavelet (MHMW) generation based on the unbalanced Mach-Zehnder interferometers (UMZIs). The analytical model, operation principle and the simulation results are presented.
Transient absorption spectroscopy with femtosecond time resolution of colloidal silver nanoparticles with diameters of 10-100 nm was accomplished. The experimental study was performed by 400 nm pump-broadband probe apparatus in spectral area of 450-600 nm at 1 mJ/cm2 excitation intensity level. The obtained picosecond relaxation times depend on particle size. The revealed electron dynamics has the...
To demonstrate light-path manipulation in arbitrary shapes, we fabricated coupled-resonator optical waveguides (CROWs) having a 90deg-corner structure on a lithographically patterned substrate using a simple self-organization process. The spectra of propagation light within the CROWs were directly measured by guide-collection-mode near-field scanning optical microscopy (NSOM) techniques. The spectra...
In this paper, we analyze bidirectional Downstream and Upstream amplification for gain transient mitigation in Remote Erbium Doped Fibre Amplifiers. Amplifying a Continuous Downstream and a burst mode Upstream data traffic in the same remotely pumped Erbium Doped Fibre Amplifier, a reduction of the overshoot and BER penalty have been experimentally measured for different packet lengths. In addition,...
In this paper, a study on a fully passive WDM/PON ring architecture which reaches 19 km distance, while serving more than 1000 users with symmetric several hundred Mbit/s per user is presented. The design is based on SARDANA (Scalable Advanced Ring -based Passive Dense Access Network Architecture) and was generated as an alternative solution, with its novelty laying on the use of L-band in line remote...
It is shown that a frequency of a plane harmonic wave transformed due to time change of the permittivity is scattered on partial spherical waves in the case of medium spherical symmetry.
The influence of optical hard-limiters using in the 2-D Wavelength/Time decoder to incoherent asynchronous optical code division multiple access system performance is evaluated by numerical modelling. General multiwavelength prime codewords are used for design the encoders and decoders. Amplitude transmission model of possible published realization of optical hard-limiters is done. The influence of...
The increasing demand for higher bit rates in access networks requires fibre deployment closer to the customer since bit rates in copper based access networks are strictly limited by the length of the copper cables. Besides higher access bit rates optical access network technologies enable extended distances between the network terminal at the customer premise and the line port at the access node...
The emerging high bandwidth and on-demand user applications require improvements in capacity, configurability and resiliency in next generation optical access networks to incrementally expand on the basis of customers requirements. New architectures and technologies are needed to achieve also scalability and active traffic adaptation. In this article an all-optical merger of access and metro networks...
We present experimental results on transmission of twenty 10 GE channels over 334 km long fibre link composed of 3 spans mixing 234 km of non-zero dispersion shifted (NZ DSF) and 100 km of standard single mode fibre (SSMF). Distributed Raman amplification in the 3 fibre spans is realized by counter-directional time division multiplexed pumping.
In this paper we review some recent results related to the application of ultra-long Raman fibre laser (URFL) cavities to quasi-lossless optical signal transmission. In an URFL, the transmission fibre itself is contained inside a laser cavity delimited by two fibre Bragg gratings, allowing for a more efficient distribution of the Raman gain to the transmitted signal. We explore the unique properties...
We review recent results on wafer fused long wavelength VCSELs emitting in the 1310 - 2000 nm range. This technology allows reaching fundamental mode output in excess of 4.5 mW at room temperature and close to 3 mW at 70degC for both the 1310 nm and 1550 nm wavebands-the highest values obtained so far. Emission wavelength can be tuned continuously with current with a tuning range as large as 15 nm...
The versatile transceiver in study for the Super Large Hadron Collider (SLHC) will have to endure severe radiation and temperature conditions while providing a high speed digital communication link to cover the experiment requirements. For this, characterization and model analysis of the electro-optic components (in particular the semiconductor laser), is of utmost importance as it will enable the...
The MQW GaInAsSb/AlGaAsSb lasers are monomodal throughout almost the whole temperature range of its operation, and they can be tuned in a wide spectral range. With the combination of the Fourier transform spectrometer and the diode lasers as sources of coherent radiation, we compared the spectra measured with a FTIR spectrometer in its absorption arrangement using a 50 W halogen lamp, with a laser...
The wireless-optical broadband-access network (WOBAN) architecture has been proposed as a flexible and cost-effective solution for future access networks. However, for WOBANs to provide geographically continuous wireless coverage it is necessary to integrate fault-tolerance in the design of such networks. In this paper we develop a heuristic algorithm to solve the problem of planning a wireless and...
The purpose of this work is to describe and demonstrate a new concept of a hybrid communication system, which consists of applying electrical CDMA to each data channel, on a system using optical WDM. Each user has a unique orthogonal CDMA code and modulates an electrical carrier (e.g. QPSK) prior to the data is used to directly modulate an optical carrier, using a laser. Therefore, it is possible...
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