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Güncel Gönderiler
Öğe Computation of Atomic Dipole Spectra for Different Atoms by Considering Short and Long Electron Trajectories under the Intense Laser Pulse(9TH INTERNATIONAL ADVANCED TECHNOLOGIES SYMPOSIUM, 2021) Sayrac, MuhammedIn this work, computation of the nonlinear dipole response of a single atom is performed by considering the ionization of the electron under the intense laser field. The dipole spectra for xenon (Xe) and argon (Ar) gases are obtained. Xe and Ar are the simples gas species having close ionization potentials. The interaction of these single atoms with the intense-short laser pulse leads to the laser-matter interaction. The short laser pulse is accepted as an ultra-short duration, i.e. the shorter time scale than the electron energy-lattice transfer process. The Keldysh parameter, which determines the ionization regime, is smaller than one because of the ionization potential of these gases. The harmonic spectra for Ar and Xe gas species are simulated by calculating the dipole spectrum considering the Lewenstein model by using a personal computer. After tunneling, the electron propagation in the short-trajectory and the combination of short and long trajectories are simulated. The effects of the short electron trajectory have noticeable effects on the dipole spectrum of a single electron.Öğe Effect of Ultrashort Laser Pulse Shape on the Dipole Spectrum of a Single Electron(International Conference on Advances in Engineering, Architecture, Science and Technology (ICAEAST 2021)), 2021) Sayrac, MuhammedIn this study, the effects of ultrashort laser pulse shape for the laser-matter interaction have been considered. Three different pulse shapes, Gaussian, Super-Gaussian, and Cosine-Squared, are used to calculate the dipole spectrum of the single atom by considering the Lewenstein model. The ultrashort laser pulse shapes are presented, and it has been found that the super-Gaussian laser pulse, which has a spiky and strong tail, has been more effective in transferring energy to the electron. The electron is excited and gains kinetic energy under the ultrashort laser pulse. The laser pulse-electron interaction affects the ground state wave function and the returning electron wave packet. The optimum dipole spectrum, which is extended to higher photon energies, has been obtained under the Super- Gaussian pulse shape.Öğe Numerical Simulation of Diffraction Patterns with Different Illumination Laser Wavelength(International Conference on Engineering Technologies (ICENTE'21), 2021) Sayrac, MuhammedIn this study, a computer simulation program generating Fresnel diffraction patterns from the apertures by using the different illumination wavelength sources has been studied. Changing the aperture-screen distance and the illumination wavelength provides a clear transition of diffraction patterns from the Fresnel to the Fraunhofer region. The diffraction patterns obtained by the Fresnel integral method have been compared with those simulated by the Fraunhofer calculation. There is a good agreement between the results. Certain conditions have been investigated that Fresnel diffraction patterns approach the Fraunhofer diffraction patterns. The simulations have been performed using a personal computer with Matlab software.
