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Ait Raiss A.,Mohammed V University | Sbai Y.,Mohammed V University | Bahmad L.,Mohammed V University | Benyoussef A.,Mohammed V University | And 2 more authors.
Journal of Magnetism and Magnetic Materials

Abstract On the basis of ab-initio calculations performed by the Akai-KKR-CPA method within the spin polarized density functional theory (DFT) and local density approximation (LDA). The magnetic and magneto-optical properties of CdTe doped with Mn and Fe, and co-doped with transitions metals (TM), have been investigated. Moreover, the density of state (DOS) have been calculated and plotted with the energy diagram, for different dopants concentrations. In this work we study, these compounds and compare our theoretical results with the experimental works concerning the doped CdTe. Then we determine which one, Mn or Fe, is responsible of the appearing magnetic and/or optical properties. We also investigate the effect of the co-doping with these elements: Mn and Fe. We show that the iron Fe does not contribute strongly in the magnetism, but it affects the optical properties of the co-doped materials. When comparing our results with the existing experimental works, we found that a low concentration of Fe improves well the magneto-optical properties such as the Faraday rotation. On the other hand, we have investigated the microscopic behavior of electrons by studying their electronic structure and density of states (DOS). © 2015 Elsevier B.V. All rights reserved. Source

Bentaleb K.,Mohammed V University | Jetto K.,Mohammed V University | Ez-Zahraouy H.,Mohammed V University | Benyoussef A.,Mohammed V University | And 2 more authors.
Chinese Physics B

The satisfaction rate of desired velocity in the case of a mixture of fast and slow vehicles is studied by using a cellular automaton method. It is found that at low density the satisfaction rate depends on the maximal velocity. However, the behavior of the satisfaction rate as a function of the coefficient of variance is independent of the maximal velocity. This is in good agreement with empirical results obtained by Lipshtat [Phys. Rev. E 79 066110 (2009)]. Furthermore, our numerical result demonstrates that at low density the satisfaction rate takes higher values, whereas the coefficient of variance is close to zero. The coefficient of variance increases with increasing density, while the satisfaction rate decreases to zero. Moreover, we have also shown that, at low density the coefficient variance depends strongly on the probability of overtaking. © 2013 Chinese Physical Society and IOP Publishing Ltd. Source

Lakhal M.,Mohammed V University | Bhihi M.,Mohammed V University | Benyoussef A.,Mohammed V University | Benyoussef A.,Institute of Nanomaterials and Nanotechnologies | And 5 more authors.
International Journal of Hydrogen Energy

Hydrogen storage ab/desorption kinetic properties of MgH2 and MgH2 doped with different metal M (M=Al,Ti,V,Fe and Ni) are investigated by using both DFT method and kinetic Monte-Carlo simulations. The first principles calculations show that the energy barriers decrease considerably when doping with a small amount of M element leading to a decreasing of both the stability and the decomposition temperature of the material. Based on the activation energies computed from DFT calculations, we show within the kinetic Monte-Carlo method that the ab/desorption time is reduced considerably without reducing much the hydrogen storage capacity of the material. From our analysis, we observed that the Ni element exhibits the most appropriate thermodynamical properties for hydrogen storage and the best kinetic of hydrogen absorption/desorption. Copyright © 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Masrour R.,App Quality | Masrour R.,Mohammed V University | Bahmad L.,Mohammed V University | Hamedoun M.,Institute of Nanomaterials and Nanotechnologies | And 4 more authors.
Solid State Communications

The magnetic properties of nanotube are investigated by Monte Carlo simulations. The nanotube is considered as a lattice of spins σ=±1/2 and S=±1,0. For each block lattice σi and Si, the blocking temperature versus values of crystal field is estimated. The magnetization of each spin configuration is computed versus the exchange interaction between the spins of each bloc lattice in the absence and the presence of crystal field at fixed temperature. In addition, the hysteresis cycle for different temperature values in the absence and presence of the crystal field is deduced. © 2013 Elsevier Ltd. Source

Masrour R.,App Quality | Masrour R.,Mohammed V University | Bahmad L.,Mohammed V University | Benyoussef A.,Mohammed V University | And 4 more authors.
Journal of Superconductivity and Novel Magnetism

The effect of the defects on magnetic properties of a bilayer Ising ferromagnetic antiferromagnetic model is studied by Monte Carlo simulations, for a nano-graphene lattice with spins that can take the values σ=3/2 and S=5/2. We consider two ferromagnetic and antiferromagnetic bilayers with N=42 spins, with a random number of defects. We only consider the nearest-neighbor interactions between the site i and j on each layer. The effects of the defects on magnetization are investigated for fixed temperature, crystal field, and magnetic field values. The thermal dependency of each layer magnetization is calculated for fixed defect rate values K 3 and K 5, the crystal field, and external magnetic field. The magnetization hysteresis loops for several rate defects are also investigated as a function of the external magnetic field. © 2012 Springer Science+Business Media New York. Source

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