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In this study, the LIBS technique was used to generate plasma from the Sn and Sn:Cr surfaces of these nanomaterials and to quantify the spectral emission of tin and chromium-containing tin. Nd-YAG laser has a wavelength of 1064 nm and a frequency of 6 Hz. After computing the plasma parameters, it was determined that the electron temperature is plasma Sn(1.286–1.819)ev and Sn: Cr (1.661-2.11505922)ev. The Sn(1.65-2.40) 108 cm -3 plasma electron density was also detected. Plasma Sn:Cr (2.85-3.39) 108cm-3 Additionally, calculations were made for plasma properties such plasma frequency, Debye length, and Debye number. At atmospheric pressure, the spectrum range of laser-induced plasma emission (200-1100 nm) was determined.

In this work, the optical emission spectrum technique was used to analyze the optical emission spectrum of (CdO: Fe) plasma produced by laser Nd: YAG with a wavelength of (532) nm, a period of 10 ns, and a focal length of 10 cm in the energy range of (200-500) mJ. The electron temperature (Te) was determined using the method of line intensities ratio. Using the Saha-Boltzmann equation, the electron density (ne) was determined. Other plasma parameters such as plasma frequency (fp), Debye length (λD) and Debye number (ND) were also measured. The CdO: Fe (at a mixing ratio of X= 0.5.) plasma spectrum was observed for different energies. As a function of the laser energies, the changes in electron temperature and densities were studied. The value of the electron temperature, at X=0.5, was (0.420 - 1.160) eV for laser energy (200-500) mJ, respectively.

This study shows the effects of copper material electrode, applied voltage, and different pressure values on electrical discharge plasma. The purpose of the work is the application of the spectral analysis method to obtain accurate results of nitrogen plasma parameters. By using the optical emission spectroscopy (OES), many N2 molecular spectra peaks appeared in the range from 300 to 480 nm. Also, some additional peaks were recorded, corresponding to atomic and ionic lines for nitrogen, target material, and hydrogen, in all samples. The electron density (ne) was calculated from the measurement of Stark broadening effect, which was found to decrease with increasing pressure from 0.1 mbar to 0.8 mbar. The higher emission intensities occurred at 0.2 mbar working pressure and were reduced with higher pressure. The vibrational temperature (Tvib) for N2 increased from 0.17 to 0.33 eV with increasing the pressure from 0.15 mbar to 0.2 mbar, then decreased to 0.25 eV with increasing the pressure to 0.8 mbar. Other plasma parameters were studied, which are electron temperature (Te), plasma frequency of electron ( ), and Debye length (λD).

The present work aims to achieve pulsed laser deposition ofTiO2 nanostructures and investigate their nonlinear properties using z-scan technique.The second harmonic Q-switched Nd: YAG laser at repetition rate of 1Hz and wavelength of 532 nm with three different laser fluencies in the range of 0.77-1.1 J/cm2 was utilized to irradiate the TiO2 target. The products of laser-induced plasma were characterized by utilizing UV-Vis absorption spectroscopy, x-ray diffraction (XRD), atomic force Microscope (AFM),and Fourier transform infrared (FTIR). A reasonable agreement was found among the data obtained usingX-Ray diffraction, UV-Vis and Raman spectroscopy. The XRD results showed that the prepared TiO2 thin films were all crystallite structure with no impurity peaks of other elements. Also, their peak intensities were increased with increasing the ablating laser fluency. AFM measurements indicated that,during pulsed laser deposition, as the laser fluency was increased, the average diameter of the prepared TiO2 nanoparticles (TiO2 NPs)was decreased from 86 to 57 nm, althoughthe differences were increased with the increase in the laser fluency. The multiphoton absorption was investigated using ultra-fast femtosecond laser with the z-scan method.The impact of thickness of the prepared films on the non-linear absorption coefficient was studied as well.

The current study was achieved on the effects of laser energy and annealing temperature on x-ray structural and optical properties, such as the UV-Visible spectra of cadmium sulfide (CdS). The films were prepared using pules laser deposition technique (PLD) under vacuum at a pressure of 2.5×10-2 mbar with different laser energies (500-800 mJ) and annealing at a temperature of 473K. X-ray diffraction patterns and intensity curves for the CdS showed that the formation of CdS multi-crystallization films at all laser energies. The optical properties of the films were studied and the variables affecting them were investigated in relation to laser energy and changes in temperature.

The production of semitransparent electrical conductive films is even more necessary due to their widespread utilization in research and industry. In this paper, the graphene oxide (GO) effects as an impurity on tin dioxide (SnO2) thin films and the SnO2–GO composite formation before and after plasma treatment have been studied to use in optoelectronic applications. The effects of graphene oxide addition and plasma treatment on the optical, electrical and structural properties of SnO2 thin films were investigated. According to the structural results of X-ray diffraction spectrum before and after applying the plasma, SnO2 thin film has a polycrystalline structure with tetragonal cassiterite phase and no peak related to impurity or other phases is seen. According to the electrical results, due to applying plasma in both pure tin oxide sample and SnO2–GO sample, the strength and resistance of the sheet decreased, but the mobility and density of the carriers increased. According to the optical results, the thin films of SnO2 show a large transfer of 75–90%, and the transfer rate is reduced by adding the graphene oxide to SnO2–GO nanocomposite. The refractive index and extinction coefficient were also evaluated for SnO2 films and SnO2–GO nanocomposite before and after plasma treatment.

The current study was carried out to reveal the plasma parameters such as ,the electron temperature ( ), electron density (ne) , plasma frequency (fp), Debye length ( ) , Debye number ( for CdS to employ the LIBS for the purpose of analyzing and determining spectral emission lines using . The results of electron temperature for CdS range (0.746-0.856) eV , the electron density(3.909-4.691)×1018 cm-3. Finally ,we discuss plasma parameters of CdS through nano second laser generated plasma .

No doubt how much importance the solar electrical energy has become and developed in the recent decades due to the continuous research in trying to maximize the ability of the CuONps based thin film solar cell in increasing its conversion efficiency. Fulfilling this requires that the porous silicon and the other various layers be integrated with each other. Remarkably optically active nanostructure of copper oxides was synthesized by pulse laser deposition (PLD). The synthesized PS and CuO/PS were characterized by using X-ray diffraction (XRD), Atomic force microscope (AFM), Reflectivity and Photoluminescence (PL) techniques. Besides, this study determines the electrical properties of prepared Al/CuO/PS/Al; namely current-voltage characteristics in dark. The average crystallite size of Copper oxide NPs was found to be 49.93 nm by AFM. According to PL spectrum, one band was observed at 738 nm and 730 nm for PS and CuO/Ps, respectively. The PL band of PS is attributed to quantum confinement. The obtained solar cell efficiency was in the range of 6.99% compared to the typical solar cell efficiency which was (2.11%). Copper may be accreditedtoplay a major role for this enhancement. These nanostructures solar cells can evolve to a new direction in photovoltaic technology.

The current study aimed the syntheses and characterizations of Gold nanoparticles (Au NPs) using a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the rod that appears for Au NPs, in addition to that, TEM has been an indication of the fact that synthesized Au NPs were spherical with a mean size of particles, ranging from 25 nm to 30 nm. At high laser pulse energy, the intensity of all emission peaks in the air at atmospheric pressure was considerably greater. Finally, variations in the operating temperature associated with the NH3 gas sensor, created from the samples that have been prepared on the sensitivity of the sensor and response time have been evaluated, the maximal sensitivity is nearly 41% concerning Au NPs that have been ablated via laser energy (E) 400 mJ on the porous silicon of the NH3 gas.

In this study, the effect of grafting with Iron (Fe) ratios (0.1, 0.3 and 0.5) on the structural and optical properties of cadmium oxide films (CdO) was studied, as these films were prepared on glass bases using the method of pulse laser deposition (PLD). The crystallization nature of the prepared films was examined by X-ray diffraction technique (XRD), which showed that the synthesis of the prepared films is polycrystalline, and Atomic Force Microscope (AFM) images also showed that the increased vaccination with Iron led to an increase in the crustal size ratio and a decrease in surface roughness, The absorption coefficient was calculated and the optical energy gap for the prepared thin films. It was found the absorption decreases and the energy gap decreases with the increase of doping ratio.

The present work investigated the discharge characteristics in the magnetized hollow cathode system. Also, the gas pressure effect on the discharge characteristics has been examined with a gas pressure between (0.08 and 0.4) Torr. The voltage-current curve of magnetized hollow cathode discharges has the voltage become approximately constant with slight increases in current. The normal glow discharge was established with constant voltage and increasing current. When the current is increased even more, then, the discharge turns into a mode comparable to the normal glow discharge between the parallel electrodes. The increasing of the pressure causes compressing of the cathode falls inside the cathode cavity and the negative glow becomes thin and more luminous. The spectroscopic method used depends on analyzing the argon’s emission atomic spectra. The electron temperature has been evaluated with the use of Boltzmann plot approach. The influence of the pressure on electron temperature observed the reduction in electron temperature when the pressure is increased. The electron number density has been calculated with the use of the Stark broadening method. The density curve indicated that the increase in electron number density with increasing of pressure until 0.4 Torr and then reduced with pressure exceeds 0.4 Torr.

This work aim to achieving laser nano-textured Si structures by means of an ultra-fast ultra-violet femtosecond (fs) laser texturing technique. The evidences of the impact of the duration of irradiation of the femtosecond laser pulses on Silicon (Si) have been investigated experimentally. A Ti:Sapphire laser at 800 nm (130 fs pulse duration with 1 kHz rate of repetition) has been employed to create nano-textured surfaces in an n-type (111) Si wafer of 0.015 Ω.cm resistivity and 508 ± 5 μm thickness. The average sizes of diameters were estimated to be in the 25−45 nm. From PL measurements of Si nanostructures, size dependent shifts in the direction of the blue spectral region have been emphasized. A highly symmetrical band shape was recognized from the samples' Raman spectra after the irradiation, the phonon frequency (phonon peak shift) shifted below 520 cm−1. The surface nanostructured Si showed lower reflectance values compared with bulk Si (un-irradiated). The observed enhancement of the fabricated Si nanostructures broad spectral response, which is in the range between the visible to the near infrared (NIR) 400−1150 nm, was attributed to increasing light absorption within sub-nanostructures. Thus, the proposed technique could be a promising approach to enhance the performance of Si-based photo-detector.

Q-switch Nd: YAG laser of wavelengths 235nm and 1,460nm with energy in the range 0.2 J to 1J and 1Hz repetition rate was employed to synthesis Ag/Au (core/shell) nanoparticles (NPs) using pulse laser ablation in water. In this synthesis, initially the silver nano-colloid prepared via ablation target, this ablation related to Au target at various energies to creat Ag/Au NPs. Surface Plasmon Resonance (SPR), surface morphology and average particle size identified employing: UV-visible spectrophotometer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorbance spectra of Ag NPs and Ag/Au NPs showed sharp and single peaks around 400nm and 410nm, respectively. The average diameter achieved for Ag/Au NPs were as 30nm and 25nm corresponding to 532nm and 1064nm, respectively. The TEM images showed that Ag/Au NPs possess a spherical shape, while the samples average size were in range from 20 to 30nm. There was an obvious increase in size during the use of 532nm laser. As for the effects of toxicity, results on human blood components showed that these nanoparticles have no effect on RBCs, WBCs and HB Therefore; these particles considered promising in the biological and medical applications.

In this work, copper substituted cobalt ferrite nanoparticles Co1-xCuxFe2O4 (×=0, 0.3, and 0.7), has been synthesized via laser assisted hydrothermal synthesis (LAHS) methods. The XRD patterns showed single phase spinel structure, comparative study between the two preparation methods, effect of laser irradiation on the structural properties, and average crystallite size that is evaluated from most intense peak (311) utilizing Scherrer formula. Further studies for laser assisted hydrothermal as-prepared ferrite samples using each of Field emission-scanning electron microscope (FE-SEM) which revealed the study of topography, shape, particle size, vibrating sample magnetometer (VSM) with in 15kOe as maximum field. That was used to study the magnetic properties and confirmed the super-paramagnetic property of the prepared ferrite nanoparticles. Coercivity (Hc), remanence (Mr), saturation magnetization (Ms) and sequarness ratio were directly extracted from hysteresis loops. Moreover, results showed that the magnetic characteristics are on the basis of each particle size as well as cation distribution. In addition, the antibacterial property of the prepared nanoparticles against S. aureus and E. coli found to be improved after substitution of Cu in Co ferrite matrix.