Abdosllam M. Abobaker

Bio: Abdosllam M. Abobaker is an academic researcher from University of Aberdeen. The author has contributed to research in topics: Photonic-crystal fiber & Dispersion (optics). The author has an hindex of 5, co-authored 24 publications receiving 106 citations. Previous affiliations of Abdosllam M. Abobaker include VIT University.

Design and Analysis of Surface-Plasmon-Resonance-Based Photonic Quasi-Crystal Fiber Biosensor for High-Refractive-Index Liquid Analytes

Abstract: We propose a sixfold photonic quasi-crystal fiber with a trapezoidal analyte channel based on surface plasmon resonance for the detection of high-refractive-index (RI) liquid analytes and numerically analyze its sensing performance for different liquid analyte refractive indices and heights using the finite-element method. In contrast to the common D-shaped structure photonic crystal fiber, we design a trapezoidal analyte channel to investigate the role of the sample liquid height within the channel and discussed the feasibility of the fabrication process. We find that with various liquid analyte heights ratios of 20%, 25%, 30%, and 50% of the maximum channel height, the proposed biosensor exhibits linear sensing performance with a maximum RI sensitivity of 4400, 6100, 8000, and 17000 nm/RIU, respectively, for analytes RI range of 1.44–1.57, 1.41–1.51, 1.40–1.49, and 1.40–1.44. This sensor is suitable to detect various high RI chemicals, biochemicals, and organic chemical samples. Owing to its simple structure of the proposed biosensor with promising linear sensing performance, we envisage that this biosensor could turn out to be a versatile and competitive instrument for the detection of high-RI liquid analytes.

A Surface Plasmon Resonance Bio-Sensor Based on Dual Core D-Shaped Photonic Crystal Fibre Embedded With Silver Nanowires for Multisensing

Abstract: In this paper, for sensing and monitoring the biochemical analyte dissolved in liquid, antigen-antibody interaction or protein-DNA/RNA binding process, we design a surface plasmon resonance refractive index based biosensor by using a dual core D-shaped six-fold photonic crystal fibre which is embedded with silver nanowires for multi-detection. We numerically analyze both the dispersion relations and the loss spectra for various analytes by finite element method. This optical fibre bio-sensor monitors the changes of the refractive index for different analytes by measuring the spectral shifts of the fibre loss peaks at their resonance wavelengths. With the wavelength interrogation method, we find that the proposed biosensor with two sensing channels exhibits a maximum refractive index sensitivity of 3400 nm/RIU and a resolution of $2.94\times 10^{-5}$ RIU for a large sensing range from 1.35 to 1.50, which covers most known analytes of proteins, viruses or DNA/RNA. By utilizing 200 nm silver nanowires in the sensing channels, the sensitivity can be enhanced up to 4000 nm/RIU. Due to its special two-channel design for multi-sensing, it is possible to distinguish/study the binding possibility/capability of unknown analyte with two different target proteins simultaneously. Further, by introducing another critical channel, the confinement loss for either channel I or channel II can be greatly enhanced for high accurate result and more reliable sensing. Moreover, we numerically prove that the diameter of nano silver wires has great influences on the sensing peaks and sensitivity of the proposed biosensor.

Influence of the Sub-Peak of Secondary Surface Plasmon Resonance Onto the Sensing Performance of a D-Shaped Photonic Crystal Fibre Sensor

Abstract: In this paper, we mainly investigate the sensing performance of a fabricable 6-fold D-shaped photonic crystal fibre sensor based on the surface plasmon resonance (SPR). Its resonance couplings between fundamental core mode and three surface plasmonic modes which have different electric filed distributions for analytes of various refractive indices have been studied in detail. We firstly observe two different types of SPRs, namely, ‘dielectric like’ resonance with low-loss peak and ‘plasmon like’ resonance with high-loss peak, by analysing the electric field distribution of the fibre modes. Then, we discuss the influence of the secondary SPR over the main SPR which is directly related to the limitation on the detection sensing range of the proposed sensor. In order to mitigate the adverse effect of the sub-peak of the secondary SPR on the sensor’s sensing performance, we reduce the thickness of analyte’s binding layer from 1500 nm to 500 nm. Thus, the sensing range of the proposed sensor can be tuned from 1.33 – 1.41 to 1.33 – 1.45 at the cost of a reduced maximum sensitivity from 7900 nm/RIU to 5300 nm/RIU. Owning to the simple structure design of the proposed sensor, we envisage that this highly sensitive D-shaped PCF-SPR sensor could be developed as a versatile and competitive instrument with a large and flexible refractive index detection range.

Exact analytical solutions for the variational equations derived from the nonlinear Schrödinger equation.

Abstract: By means of the variational formalism for the nonlinear Schrodinger equation, we find an explicit relation for the power of a pulse in terms of its duration, chirp and fiber parameters (group-velocity dispersion and self-phase modulation parameters). Then, using that relation, we derive the explicit analytical expressions for the variational equations corresponding to the amplitude, width, and chirp of the pulse. The derivation of the analytical expressions for the variational equations is possible for the condition when the Hamiltonian of the system is zero. Finally, for Gaussian and hyperbolic secant ansatz, we show good agreement between the results obtained from the analytical expressions and the direct numerical simulation of the nonlinear Schrodinger equation.

Progress in optics

Abstract: Have you ever felt that the very title, Progress in Optics, conjured an image in your mind? Don’t you see a row of handsomely printed books, bearing the editorial stamp of one of the most brilliant members of the optics community, and chronicling the field of optics since the invention of the laser? If so, you are certain to move the bookend to make room for Volume 16, the latest of this series. It contains seven chapters on widely diverging topics, written by well-known authorities in their fields. These are: 1) Laser Selective Photophysics and Photochemistry by V. S. Letokhov, 2) Recent Advances in Phase Profiles (sic) Generation by J. J. Clair and C. I. Abitbol, 3 ) Computer-Generated Holograms: Techniques and Applications by W.-H. Lee, 4) Speckle Interferometry by A. E. Ennos, 5 ) Deformation Invariant, Space-Variant Optical Pattern Recognition by D. Casasent and D. Psaltis, 6) Light Emission from High-Current Surface-Spark Discharges by R. E. Beverly, and 7) Semiclassical Radiation Theory within a QuantumMechanical Framework by I. R. Senitzkt. The breadth of topic matter spanned by these chapters makes it impossible, for this reviewer at least, to pass judgement on the comprehensiveness, relevance, and completeness of every chapter. With an editorial board as prominent as that of Progress in Optics, however, it seems hardly likely that such comments should be necessary. It should certainly be possible to take the authority of each author as credible. The only remaining judgment to be made on these chapters is their readability. In short, what are they like to read? The first sentence of the first chapter greets the eye with an obvious typographical error: “The creation of coherent laser light source, that have tunable radiation, opened the . . . .” Two pages later we find: “When two types of atoms or molecules of different isotopic composition ( A and B ) have even one spectral line that does not overlap with others, it is pos-

Applications of nonlinear fiber optics

Abstract: * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The book presents sound coverage of the fundamentals of lightwave technology, along with material on pulse compression techniques and rare-earth-doped fiber amplifiers and lasers. The extensively revised chapters include information on fiber-optic communication systems and the ultrafast signal processing techniques that make use of nonlinear phenomena in optical fibers.New material focuses on the applications of highly nonlinear fibers in areas ranging from wavelength laser tuning and nonlinear spectroscopy to biomedical imaging and frequency metrology. Technologies such as quantum cryptography, quantum computing, and quantum communications are also covered in a new chapter.This book will be an ideal reference for: RD scientists involved with research on fiber amplifiers and lasers; graduate students and researchers working in the fields of optical communications and quantum information. * The only book on how to develop nonlinear fiber optic applications* Two new chapters on the latest developments; Highly Nonlinear Fibers and Quantum Applications* Coverage of biomedical applications

Supercontinuum generation, photonic crystal fiber

Abstract: A topical review of numerical and experimental studies of supercontinuum generation in photonic crystal fiber is presented over the full range of experimentally reported parameters, from the femtosecond to the continuous-wave regime. Results from numerical simulations are used to discuss the temporal and spectral characteristics of the supercontinuum, and to interpret the physics of the underlying spectral broadening processes. Particular attention is given to the case of supercontinuum generation seeded by femtosecond pulses in the anomalous group velocity dispersion regime of photonic crystal fiber, where the processes of soliton fission, stimulated Raman scattering, and dispersive wave generation are reviewed in detail. The corresponding intensity and phase stability properties of the supercontinuum spectra generated under different conditions are also discussed.

A Hi-Bi Ultra-Sensitive Surface Plasmon Resonance Fiber Sensor

Abstract: In this paper, a simple, miniature, and highly sensitive photonic crystal fiber (PCF)-based surface plasmon resonance (SPR) sensor is proposed. The target analyte and the plasmonic material are at the outer surface of the fiber making practical applications feasible. A 30-nm gold (Au) layer supports surface plasmons. A thin titanium dioxide (TiO 2 ) layer is used to assist adhesion of Au on the glass fiber. The fiber cross section is formed purely by circular-shaped holes simplifying the preform manufacturing process. A high-birefringence (hi-bi) fiber is obtained by means of an array of air holes at the center of the fiber. A finite element method (FEM) is employed to analyze the surface plasmon properties of the proposed PCF-SPR sensor. By optimizing the geometric parameters, a maximum wavelength sensitivity (WS) of 25 000 nm/RIU and an amplitude sensitivity (AS) of 1411 RIU -1 for a dielectric refractive index (RI) range of 1.33-1.38 are obtained. Moreover, an estimated maximum resolution of 4 × 10 -6 and a figure of merit (FOM) of 502 are obtained that ensures high detection accuracy of small refractive index (RI) changes. Owing to its sensitivity and simple architecture, the proposed sensor has potential application in a range of sensing application, including biosensing.