Jalil Ali

ENHANCEMENT OF FSR AND FINESSE USING ADD/DROP FILTER AND PANDA RING RESONATOR SYSTEMS

We present effect of the input central wavelength on microring resonator (MRR) performance using proposed systems. The first proposed system consists of series of microring resonator incorporated with an add/drop filter system, while the second system uses a PANDA ring resonator connected to an add/drop filter system. These two systems can be used to enhance the free spectrum range (FSR) and finesse (F) of the optical soliton pulses. The FSR and Finesse can be improved by raising the central wavelengths of the input pulse from 0.6 μm to 1.5 μm. This is obtained via the add/drop filter, which is used to increase the channel capacity of the communication networks as well. Simulation results for the first proposed system show that FSR and FWHM of 1530 pm and 50 pm can be obtained when the central wavelength of the input pulse is 1.5 μm. FSR and FWHM of 370 pm and 5 pm are simulated, when the PANDA ring resonator system is used. Therefore Finesse of the systems can be improved to 30.6 and 74 for the first and second proposed system, respectively.

IEEE 802.15.3c WPAN Standard Using Millimeter Optical Soliton Pulse Generated by a Panda Ring Resonator

A system of microring resonators (MRRs) connected to an optical modified add/drop filter system known as a Panda ring resonator is presented. The optical soliton pulse of 60 GHz frequency band can be generated and used for Wireless Personal Area Network (WPAN) applications such as IEEE 802.15.3c. The system uses chaotic signals generated by a Gaussian laser pulse propagating within a nonlinear MRRs system. The chaotic signals can be generated via a series of microring resonators, where the filtering process is performed via the Panda ring resonator system wherein ultrashort single and multiple optical soliton pulses of 60 GHz are generated and seen at the through and drop ports, respectively. The IEEE 802.15.3c standard operates at the 60 GHz frequency band, and it is applicable for a short distance optical communication such as indoor systems, where the higher transmission data rate can be performed using a high frequency band of the output optical soliton pulses. The single and multi-soliton pulses could be generated and converted to logic codes, where the bandwidths of these pulses are 5 and 20 MHz, respectively. Thus, these types of signals can be used in optical indoor systems and transmission link using appropriate components such as transmitter, fiber optics, amplifier, and receiver.

ASK-to-PSK generation based on nonlinear microring resonators coupled to one MZI arm

We present a new concept of ASK‐to‐PSK generation based on nonlinear microring resonators coupled to one MZI arm by using OptiWave FDTD method. By microring resonator increase from one to three microring (SR to TR), we found that the amplitude shift keying (ASK) are increase exactly and the phase shift keying (PSK) is equal to π.

All-Optical OFDM Generation for IEEE802.11a Based on Soliton Carriers Using Microring Resonators

The optical carrier generation is the basic building block to implement all-optical orthogonal frequency-division multiplexing (OFDM) transmission. One method to optically generate single and multicarriers is to use the microring resonator (MRR). The MRRs can be used as filter devices, where generation of high-frequency (GHz) soliton signals as single and multicarriers can be performed using suitable system parameters. Here, the optical soliton in a nonlinear fiber MRR system is analyzed, using a modified add/drop system known as a Panda ring resonator connected to an add/drop system. In order to set up a transmission system, i.e., IEEE802.11a, first, 64 uniform optical carriers were generated and separated by a splitter and modulated; afterward, the spectra of the modulated optical subcarriers are overlapped, which results one optical OFDM channel band. The quadrature amplitude modulation (QAM) and 16-QAM are used for modulating the subcarriers. The generated OFDM signal is multiplexed with a single-carrier soliton and transmitted through the single-mode fiber (SMF). After photodetection, the radio frequency (RF) signal was propagated. On the receiver side, the RF signal was optically modulated and processed. The results show the generation of 64 multicarriers evenly spaced in the range from 54.09 to 55.01 GHz, where demodulation of these signals is performed, and the performance of the system is analyzed.

Blood cleaner on-chip design for artificial human kidney manipulation

A novel design of a blood cleaner on-chip using an optical waveguide known as a PANDA ring resonator is proposed. By controlling some suitable parameters, the optical vortices (gradient optical fields/wells) can be generated and used to form the trapping tools in the same way as optical tweezers. In operation, the trapping force is formed by the combination between the gradient field and scattering photons by using the intense optical vortices generated within the PANDA ring resonator. This can be used for blood waste trapping and moves dynamically within the blood cleaner on-chip system (artificial kidney), and is performed within the wavelength routers. Finally, the blood quality test is exploited by the external probe before sending to the destination. The advantage of the proposed kidney on-chip system is that the unwanted substances can be trapped and filtered from the artificial kidney, which can be available for blood cleaning applications.

ALL-OPTICAL SWITCHES BASED ON GaAs/AlGaAs QUANTUM DOTS VERTICAL CAVITY

In this paper, an all-optical switch based on self-assembled GaAs/AlAs quantum dots (QDs) within a vertical cavity is designed and proposed. Two essential aspects of this novel device have been investigated, which include the QD/cavity nonlinearity with appropriately designed mirrors and the intersubband carrier dynamics inside QDs. The vertical-reflection-type switches have been investigated with an asymmetric cavity that consists of 12 periods of GaAs/Al0.8Ga0.2As and 25 periods for the front and back mirrors, respectively. The thicknesses of the GaAs and AlGaAs layers are chosen to be 89 and 102 nm, respectively. To give a dot-in-a-well (DWELL) structure, the 65 nm dimension of Si was recommended to deposit within a 20 nm AlAs QW. Results obtained have shown that all-optical switching via the QD excited states has been achieved with a time constant down to 275-fs and over 29.5 nm tunable wavelengths. These results demonstrated that QDs within a vertical cavity have great potential to realize low-power, consumption polarization-insensitive and micrometer-sized switching devices for future optical communication and signal processing systems.

Atom Bottom-Up Manipulation Controlled by Light for Microbattery Use

In this paper, we propose a new design of the atom bottom-up technique that uses an optical trapping tool to form the atom trapping layer within a thin-film grating. By using a PANDA ring resonator, where atoms can be trapped, pumped, and controlled by light, the trapped atoms/molecules can be selected, filtered, and embedded within the required thin-film grating layers to manufacture nanobattery. In application, P-type or N-type atom can be prepared, trapped, and embedded within the desired thin-film layers, and finally, the microbattery can be manipulated. The theoretical background of light pulse in a PANDA ring resonator is also reviewed.

Laser-Induced Plasma and its Applications

The laser irradiation have shown a range of applications from fabricating, melting, and evaporating nanoparticles to changing their shape, structure, size, and size distribution. Laser induced plasma has used for different diagnostic and technological applications as detection, thin film deposition, and elemental identification. The possible interferences of atomic or molecular species are used to specify organic, inorganic or biological materials which allows critical applications in defense (landmines, explosive, forensic (trace of ex‐ plosive or organic materials), public health (toxic substances pharmaceutical products), or environment (organic wastes). Laser induced plasma for organic material potentially provide fast sensor systems for explosive trace and pathogen biological agent detection and analysis. The laser ablation process starts with electronic energy absorption (~fs) and ends at particle recondensation (~ms). Then, the ablation process can be governed by thermal, non-thermal processes or a combination of both. There are several types of mod‐ els, i.e., thermal, mechanical, photophysical, photochemical and defect models, which de‐ scribe the ablation process by one dominant mechanism only. Plasma ignition process includes bond breaking and plasma shielding during the laser pulse. Bond breaking mechanisms influence the quantity and form of energy (kinetic, ionization and excitation) that atoms and ions can acquire. Plasma expansion depends on the initial mass and ener‐ gy in the plume. The process is governed by initial plasma properties (electron density, temperature, velocity) after the laser pulse and the expansion medium. During first mi‐ crosecond after the laser pulse, plume expansion is adiabatic afterwards line radiation be‐ comes the dominant mechanism of energy loss.

Fibre Bragg grating and no-core fibre sensors

Introduction -- Literature Review -- Theory -- Methodology -- Indoor Fibre Bragg Grating Temperature Sensor -- Outdoor Fibre Bragg Grating Temperature Sensor -- Conclusion.

Micro-Slit Based Coherent Detection of Terahertz Pulses in Biased, Solid State Media

We demonstrated coherent Terahertz characterization based on the Terahertz Field Induced Second Harmonic effect in few microns thick Silica (SiO2) samples that can be easily operated with as little as a few hundred Volts. Our sample is an infinitely long 30 μm slit written in gold. The underlying idea of our work is that of exploiting the large breakdown voltage and the high nonlinearity of glass to achieve a large signal to noise ratio detection with a very weak optical probe at moderate bias fields, thus drastically reducing the electrodes gap. Our results pave the way to a novel approach towards broadband THz detection.