Optimal Behavior of Spectral Line Analysis Through Fine Identification of Heavy Metal Lines in Crude Oil Using LIPS-Technique

Assessment of the quality of minerals, especially heavy ones, in crude oil by identifying spectral lines is very important to determine the quality and specifications of crude oil and the following treatments in production of the lines. In this study heavy metals lines (HMs) found in crude oil extracted from Iraq south field were identified that are unique spectral lines by using the laser-induced plasma spectroscopy (LIPS – mechanism), which were analyzed later by spectrometer based on the principle of finger print. The optimum spectrum (analytical lines) of metals emitted from the crude oil plasma in air were selected and determined. By determining the optimization behavior for evaluation procedure, the important condition was laser spot number (scan area). Comparison was performed between the fundamental wavelength and harmonic generation (HG) used in the laser beam to determine the optimum spectrum and optical insulator to cover the selected sample at atmospheric air pressure and room temperature. The results obtained from the actual raw spectrum were determined to represent the emission lines without the influence of foreign light (no noise) using the optical isolator, and unique new analytical lines were identified when increasing the number of lasers points up to 5 points, and a balanced spectrum was determined with good absorption when using a basic wavelength of 1064 nm. Difficulties were presented due to the characteristics of the crude oil as organic liquid case. The optimum results obtained indicated that the LIPS technique is effective and a control technique to well identify the spectrum lines of the heavy metals (HMs) presented in the crude oil.

High power supercontinuum generation by dual-color femtosecond laser pulses in fused silica

High power supercontinuum (SC) is generated by focusing 800 nm and 400 nm femtosecond laser pulses in fused silica with a microlens array. It is found that the spectrum of the SC is getting broader compared with the case of single laser pulse, and the spectral energy density between the two fundamental laser wavelengths is getting significantly higher by optimizing the phase matching angle of the BBO. It exceeds μJ/nm over 490 nm range which is from 380 nm to 870 nm, overcoming the disadvantage of relative lower power in the ranges far from fundamental wavelength.

Enhancement of second harmonic generation in a layered MoS2 nanoresonator

Molybdenum disulfide (MoS2) is a layered material with a high refractive index in the visible and infrared spectral range. In this work, we theoretically and experimentally demonstrate Mie-resonant MoS2 nanodisks. We show enhanced second harmonic generation from MoS2 nanodisk resonators due to the overlap of Mie-type resonances at the fundamental wavelength with the C-exciton resonance at the second-harmonic wavelength.

Analysis of linear and non-linear effects in the frequency domain for a three-channel optical transmission system

This paper presents the analysis of a wavelength division multiplexer communication system in the frequency domain, with the objective of visualizing the incidence of the linear phenomena of attenuation and chromatic dispersion, together with the phenomenon of phase self-modulation, the Kerr electro-optical effect and fourth wave mixing. The analyzed system consists of a laser transmitter with a Mach-Zender modulator and a standard G.625b single-mode fiber link transmitting three optical signals of 10 mW, 25 mW and 50 mW at a fundamental wavelength of 1550 nm at a rate of 10 Gbps. This system is analyzed through a graphical user interface programmed by the authors in the Python environment, which calculates the parameters corresponding to each phenomenon and graphically represents the transmission results at distances of 50 km and 100 km. The analysis methodology consists of varying the spectral separation of the transmitted channels, initially considering a spectral separation of 2 nm and subsequently a spectral separation of 0.2 nm, observing as a result that the harmonics generated by the fourth wave mixing phenomenon considerably alter the spectral density of the transmitted signals, since the energy of the harmonics is equal to the power of the transmitted signals. On the other hand, with the spectral spacing of 0.2 nm, it is obtained that, although the harmonics alter the spectral density waveform, the bandwidth is not compromised by these additional signals.

Relaxing symmetry rules for nonlinear optical interactions via strong light-matter coupling

Transition Metal Dichalcogenides (TMDCs) have been in the limelight for the past decade as a candidate for several optoelectronic devices, and as a versatile test bed for various fundamental light-matter interaction phenomena thanks to their exceptional linear optical properties arising from their large binding energy, strong spin-orbit coupling and valley physics in the monolayer (ML) limit. They also boast strong non-linear properties fortied by excitonic responses in these systems. However, the strong second order non-linear responses are mostly restricted to the ML limit owing to crystal symmetry requirements, posing several limitations in terms of smaller interaction length and lower damage threshold. Here we demonstrate a self-hybridized exciton-polariton system in bulk WSe2 that allows us to relax the crystal symmetry rules that govern second order non-linearities. The demonstrated polariton system shows intense Second Harmonic Generation (SHG) when the fundamental wavelength is resonant with the lower polariton, with an efficiency comparable to the one from a ML WS2 when excited at the same fundamental wavelength and intensity. We model this phenomenon by considering a system with alternating second- order susceptibilities under an asymmetric electric field profile determined by the polariton mode. Helicity resolved polarization experiments show very similar non-linear response as the one from a ML where the helicity of the SHG flips with respect to the fundamental harmonic. This polaritonic system offers a platform to leverage robust second order non-linear response from centrosymmetric systems, while at the same time allowing access to third-order non-linearity inherent in strongly coupled systems.

Anti-Reflection Nanostructures on Tempered Glass by Dynamic Beam Shaping

Reflectivity and surface topography of tempered glass were modified without any thermal damage to the surroundings by utilizing 1.7 ps ultrashort pulsed laser on its fundamental wavelength of 1030 nm. To speed up the fabrication, a dynamic beam shaping unit combined with a galvanometer scanning head was applied to divide the initial laser beam into a matrix of beamlets with adjustable beamlets number and separation distance. By tuning the laser and processing parameters, reflected intensity can be reduced up to 75% while maintaining 90% of transparency thus showing great potential for display functionalization of mobile phones or laptops.

ANNEALING TEMPERATURE ENHANCED THE CONVERSION EFFICIENCY OF (ITO/ZNO/CUO) HETEROJUNCTION

Copper oxide (CuO) thin film was deposited on glass substrates using pulsed laser deposition by fundamental wavelength (1064 nm) Q-switched Nd:YAG laser with 900 mJ peak energy at RT and annealed at 200 and 300 ᴼC respectively. The Structural and optical properties of the prepared copper oxide thin films were studied using X-ray diffraction (XRD) and energy UV-visible spectroscopy. The copper oxide films exhibited Cu2O phase of cubic structure converted gradually to CuO in a monoclinic crystal structure when annealed to 300 ᴼC. Direct energy gap 2.25 eV value at RT sample, While the annealed samples have 1.8 and 1.6 eV indirect transitions. The I-V Characteristics of the ZnO/CuO heterojunction were studied under illumination revealed that the fabricate samples exhibit photovoltaic properties. The best efficiency appeared at 200 ᴼC annealing temperature

Spectroscopic Investigation of Laser-Induced Graphene Plasma

In this paper, graphene plasma was obtained through the interaction of the fundamental radiation from a pulsed Nd:YAG laser at the fundamental wavelength of 1064 nm focused onto a solid plane of graphene material. This reaction was carried out under conditions of an atmospheric status. The resulting plasma was tested using an optical emission spectroscopy technique. The temperature of the electrons is calculated by the tow line ratio of C I and C II emission lines singly ionised, and the density of the plasma electron is calculated with Saha-Boltzmann equation. The upper limit of the electron temperature was approximately 1.544 eV. The corresponding electron density was 11.5×1015 cm-3. Then the electron temperature decreased when the energy was 300 mJ and it was near 1.462 eV, corresponding to the density of those electrons 8.7×1015 cm-3.

Synthesis and Characterization of Gallium Oxide Nanoparticles using Pulsed Laser Deposition

In this paper, the productions of gallium oxide (Ga2O3) nanoparticles were achieved via using the Nd: YAG laser deposition method with a fundamental wavelength (1064 nm). These nanoparticles were characterized by using different methods such as X-ray diffractometer (XRD), atomic force microscopy (AFM) and Ultraviolet–visible (UV–vis) spectroscopy. To examine the effects of laser energy on the properties of nanoparticles, the experimental results and theoretical considerations were prepared by the effective method of pulse laser deposition. The synthesis of Ga2O3NPs) was achieved with different ranges of energies (500 to 900 mJ). Average crystallite sizes of the synthesized nanoparticles were found to be in the range of 15-37 nm. On the other hand, the AFM images showed that the size is ranging between 60 and 85 nm. Optical parameters of the samples showed a strong dependence on average crystallite size.

Synthesis of Graphene Oxide Nanoparticles by Laser Ablation System

In this study, graphene oxide (GO) and reduced graphene oxide were synthesized by pulsed Nd:YAG laser with a fundamental wavelength (1064 nm) focused on the pure graphite target which was immersed in distilled water. Different pulse energies were applied in two cases; with and without magnetic field. The synthesized GO and rGO nanoparticles were characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) with and without magnetic field. The data show the presence of a magnetic field which illustrated increasing oxygen functional groups of GO. This caused a change in the morphology of the surface of GO, increasing crystallite size from 12.19 nm to 71.2 nm. The interlayer distance (d-space) was reduced from 0.4 nm to 0.25 nm and the absorption peaks that appeared in the spectrum were reduced and shifted toward smallest wavelengths, while the stretching vibration of the O-H group peak was shifted toward largest wavelengths.