We demonstrate the results of a mathematical model for investigation the nonlinear Stimulated Brillouin Scattering (SBS), which can be employed to achieve high optical amplifier. The SBS is created by interaction between the incident We demonstrate the results of a mathematical model for investigation the nonlinear Stimulated Brillouin Scattering (SBS), which can be employed to achieve high optical amplifier. The SBS is created by interaction between the incident light and the acoustic vibration fiber. The design criteria and the amplification characteristic of the Brillouin amplifier is demonstrated and discussed for fiber Brillouin amplifier using different pump power with different fiber length. The results show, high Brillouin gain can be achieved with high pump power and long effective fiber length.and the acoustic vibration fiber. The design criteria and the amplification characteristic of the Brillouin amplifier is demonstrated and discussed for fiber Brillouin amplifier using different pump power with different fiber length. The results show, high Brillouin gain can be achieved with high pump power and long effective fiber length.
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The effect of adding different volume of coumarin dye (5, 15, 25 and 35) ml on optical properties of Poly (Methyl Meth Acrylate) was studied. Films of pure PMMA and PMMA with different volume of coumarin dye (5, 15, 25 and 35) ml were prepared using the casting technique. Transmission and absorption of the films were measured by using UV-VIS spectrometer technique type (100 Conc), in order to assess the type of transmission which was found an indirect transition. An optical energy gap of pure PMMA is (4.95e v) and after adding coumarin with volume (25, 35) ml, the energy gap for PMMA decrease by (0.05) compere to pure PMMA films and addition energy gap appear equal to (4.1 e v). It was found that the absorption coefficient, extinction coeff
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Thin films of the blended solution of (NiPc/C60) on glass substrates were prepared by spin-coated method for three different ratios (100/1, 100/10 and 100/100). The effects of annealing temperature and C60 concentration on the optical properties of the samples were studied using the UV-Vis absorption spectroscopy and FTIR spectra. The optical absorption spectrum consists of two main bands, Q and B band, with maxima at about (602-632) nm and (700-730) nm for Q1 and Q2 respectively, and (340-375) nm for B band. The optical energy gap were determined from optical absorption spectra, The variation of optical energy gap with annealing temperature was nonsystematic and this may be due to the improvement in crystal structure for thin films. Whi
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Thin films of pure tin mono-sulfide SnS and tin mono-sulfide for (1,2,3,4)% fluorine SnS:F with Thicknesses of (0.85 ±0.05) ?m and (0.45±0.05) ?m respectively were prepared by chemical spray pyrolysis technique. the effect of doping of F on structural and optical properties has been studied. X-Ray diffraction analysis showed that the prepared films were polycrystalline with orthorhombic structure. It was found that doping increased the intensity of diffraction peaks. Optical properties of all samples were studied by recording the absorption and transmission spectrum in range of wave lengths (300-900) nm. The optical energy gap for direct forbidden transi
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Alloys of InxSe1-x were prepared by quenching technique with
different In content (x=10, 20, 30, and 40). Thin films of these alloys
were prepared using thermal evaporation technique under vacuum of
10-5 mbar on glass, at room temperature R.T with different
thicknesses (t=300, 500 and 700 nm). The X–ray diffraction
measurement for bulk InxSe1-x showed that all alloys have
polycrystalline structures and the peaks for x=10 identical with Se,
while for x=20, 30 and 40 were identical with the Se and InSe
standard peaks. The diffraction patterns of InxSe1-x thin film show
that with low In content (x=10, and 20) samples have semi
crystalline structure, The increase of indium content to x=30
decreases degree o
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Cadmium sulfide (CdS) thin films with n-type semiconductor characteristics were prepared by flash evaporating method on glass substrates. Some films were annealed at 250 oC for 1hr in air. The thicknesses of the films was estimated to be 0.5µ by the spectrometer measurement. Structural, morphological, electrical, optical and photoconductivity properties of CdS films have been investigated by X-ray diffraction, AFM, the Hall effect, optical transmittance spectra and photoconductivity analysis, respectively. X-ray diffraction (XRD) pattern shows that CdS films are in the stable hexagonal crystalline structure. Using Debye Scherrerś formula, the average grain size for the samples was found to be 26 nm. The transmittance of the
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a-Ge: As thin films have prepared by thermal evaporation teclmique, then they were annealing at various temperatures within the
range (373-473) K. The result of X-ray di ffraction spectrum was showing that all the specimens remained in amorphous structure before and after annealing process. This paper studied the effect of annealing temperature as a function of wavelength on the optical energy gap and optical constants for the a-Ge:As thin films . Results have showed that there was an increasing in the optical energy gap
{Egopt) values with the in ,;rcasing of the annealing temperatures within
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