The change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.

     The fabricated Photodetector n-CdO /-Si factory thin films Altboukaraharara spatial silicon multi- crystallization of the type (n-Type) the deposition of a thin film of cadmium and at room temperature (300K) and thickness (300 ± 20nm) and the time of deposition (1.25sec) was antioxidant thin films cadmium (Cd) record temperature (673k) for one hour to the presence of air and calculated energy gap optical transitions electronic direct ( allowed ) a function of the absorption coefficient and permeability and reflectivity by recording the spectrum absorbance and permeability of the membrane record within the wavelengths (300 1100nm). was used several the bias ranged between 1-5 Volts. The results showed that this

This study is dedicated to investigate the effects of initial laser intensity on the nonlinear optical properties of the laser dye DQOCI dissolved in methanol with a concentration of 10 ^-5 M and doped with PMMA film. The properties were studied by using open and closed aperture Z-scan technique, with different levels of initial intensity (I₀), excited by continuous diode solid-state laser at a wavelength of 532 nm. Three lenses of different focal lengths were employed to change the radius of the Gaussian laser beam and then change the initial intensity. For I₀= 6.83 and 27.304 kWatt/cm², the Z-scan curves show a saturation of absorption (SA) known as the negative type of nonlinearity, in which

Pure cadmium oxide films (CdO) and doped with zinc were prepared at different atomic ratios using a pulsed laser deposition technique using an ND-YAG laser from the targets of the pressed powder capsules. X-ray diffraction measurements showed a cubic-shaped of CdO structure. Another phase appeared, especially in high percentages of zinc, corresponding to the hexagonal structure of zinc. The degree of crystallinity, as well as the crystal size, increased with the increase of the zinc ratio for the used targets. The atomic force microscopy measurements showed that increasing the dopant percentage leads to an increase in the size of the nanoparticles, the particle size distribution was irregular and wide, in addition, to increase the surfac

In this Research, (In₂O₃: CdO) films were prepared using pulsed laser deposition (PLD) method on glass substrate at room temperature deposited at laser influence 500mJ/cm²with different shoots N= (200,300,400,500and600). the structural, and the optical properties and the films are studied with different annealing temperatures (523and 623) K. Optical measurements and the films were analyzed by UV-VIS absorption spectra. The structural properties of samples were investigated by x-ray diffraction patterns of the films and show that the films and polycrystalline Structure with all shoots. Transmittance spectrum found is equal to 93.17%, refractive index range is 1.635 and energy gap range is 2.75-3.15ev.

We have studied the synthesis environment of ambient pressure silica aerogels influence on their resulting morphological and optical properties. Transparent nanoporous silica aerogel was synthesized at ambient pressure using tetraethylorthosilicate precursor via a sol-gel process. Effect of drying control chemical additives and catalyst on physical properties was investigated. Trimethylchlorolsilane was employed as a hydrophobic reagent in the surface modification process. All aerogel samples were prepared utilizing a subcritical procedure under reactant pH fixed at 8.3, using just ammonium hydroxide or together with ammonium fluoride as catalyst. The effects catalyst types as well as drying control chemical additives on the physical pro

 Zinc oxide (ZnO) transparent thin films with different oxygen flow rates (0.5, 1.0, and 1.5)Litter/min. were prepared by thermal evaporation technique on glass substrate at a temperature of 200℃ with rate (10±2)nm sec-1,  The crystallinity and structure of these films were analyzed  by X-ray diffraction (XRD). It exhibits a polycrystalline hexagonal wurtzite structure and the preferred orientation along (002) plane. The Optical properties of ZnO were determined through the optical transmission method using ulta violet–Visible spectrophotometer with in wave length (300-1100)nm. The optical transmittance of the ZnO films increases from 75% to 85% with increase flow rate of O2, and the optical band gap of ZnO