The pure and Sb doped GeSe thin films have been prepared by thermal flash evaporation technique. Both the structural and optical measurement were carried out for as deposited and annealed films at different annealing temperatures.XRD spectra revealed that the all films have one significant broad amorphous peak except for pure GeSe thin film which annealed at 573 K, it has sharp peak belong to orthorhombic structure nearly at 2θ=33o. The results of the optical studies showed that the optical transition is direct and indirect allowed. The energy gap in general increased with increasing annealing temperature and decreased with increase the ratio of Sb dopant. The optical parameters such as refractive index, extinction coefficient and real and
... Show MoreIn this work ,the modified williamos-Hall method was used to analysis the x-ray diffraction lines for powder of magnesium oxide nanoparticles (Mgo) .and for diffraction lines (111),(200),(220),(311) and (222).where by used special programs such as origin pro Lab and Get Data Graph ,to calculate the Full width at half maximum (FWHM) and integral breadth (B) to calculate the area under the curve for each of the lines of diffraction .After that , by using modified Williamson –Hall equations to determin the values of crystallite size (D),lattice strain (ε),stress( σ ) and energy (U) , where was the results are , D=17.639 nm ,ε =0.002205 , σ=0.517 and U=0.000678 respectively. And then using the scherrer method can by calculated the crystal
... Show MoreMany designs have been suggested for unipolar magnetic lenses based on changing the width of the inner bore and fixing the other geometrical parameters of the lens to improve the performance of unipolar magnetic lenses. The investigation of a study of each design included the calculation of its axial magnetic field the magnetization of the lens in addition to the magnetic flux density using the Finite Element Method (FEM) the Magnetic Electron Lenses Operation (MELOP) program version 1 at three different values of current density (6,4,2 A/mm2). As a result, the clearest values and behaviors were obtained at current density (2 A/mm2). it was found that the best magnetizing properties, the high
... Show MoreOptical fiber technology is without a doubt one of the most significant phases of the communications revolution and is crucial to our daily lives. Using the free version (2022) of RP Fiber Calculator, the modal properties for optical fibers with core radii (1.5−7.5) μm, core index (1.44−1.48) and cladding index (1.43−1.47) have been determined at a wavelength of 1000 nm. When the fiber core’s radius is larger than its operating wavelength, multimode fibers can be created. The result is a single-mode fiber in all other cases. All of the calculated properties, it has been shown, increase with increasing core radius. The modes’ intensity profiles were displayed.
In the present work we prepared heterojunction not homogenous CdS/:In/Cu2S) by spray and displacement methods on glass substrate , CdS:In films prepared by different impurities constration. Cu2S prepared by chemical displacement method to improve the junction properties , structural and optical properties of the deposited films was achieved . The study shows that the film polycrystalline by XRD result for all film and the energy gap was direct to 2.38 eV with no effect on this value by impurities at this constration .
A nanocrystalline CdS thin film with 100 nm thickness has been prepared by thermal evaporation technique on glass substrate with substrate temperature of about 423 K. The films annealed under vacuum at different annealing temperature 473, 523 and 573 K. The X-ray diffraction studies show that CdS thin films have a hexagonal polycrystalline structure with preferred orientation at (002) direction. Our investigation showed the grain size of thin films increased from 9.1 to 18.9 nm with increasing the annealing temperature. The optical measurements showed that CdS thin films have direct energy band gap, which decreases with increasing the annealing temperature within the range 3.2- 2.85 eV. The absorbance edge is blue shifted. The absorption
... Show MoreThe Bi2Se3 compound was synthesis by fusing initial compounds consisting of
extra pure elements in stoichiometric ratio from elements compound, charged inside
quartz ampoule. The crystal growth of Bi2Se3 carried out using Brighaman technique
process from melting f (Bi+Se ) at temperature of 810 ºC for about 48 hrs. Single crystal
of Bi2Se3 has been grown in direction (211) after slow cooling on account of heat
gradient to zone furnaces at cooling rate (1-3) C/hr. The structure study of the compound
was determined by x-ray diffraction technique, which it has bismuthinite structure and
orthorhombic unit cell with lattice parameters of a=10.2678 Å, b=11.2392 Å and
c=5.1737 Å