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Masrour R.,App Quality | Jabar A.,App Quality | Bahmad L.,Mohammed V University | Hamedoun M.,Institute of Nanomaterials and Nanotechnologies | And 2 more authors.
Journal of Magnetism and Magnetic Materials | Year: 2017

In this paper, we study the magnetic properties of ferrimagnetic mixed spins with integer σ=2 and half-integer S=7/2 in a Blume–Capel model, using Monte Carlo simulations. The considered Hamiltonian includes the first nearest-neighbors and the exchange coupling interactions on the two sub-lattices. The effect of these coupling exchange interactions, in the presence of both the external magnetic field and the crystal field, are studied. The magnetizations and the corresponding susceptibilities are presented and discussed. Finally, we have interpreted the behaviors of the magnetic hysteresis of this model. © 2016 Elsevier B.V.


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 | Year: 2013

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.


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.
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2014

The magnetic properties of ferromagnetic Ni/Au core/shell have been studied using Monte Carlo simulations within the Ising model framework. The considered Hamiltonian includes the exchange interactions between Ni-Ni, Au-Au and Ni-Au and the external magnetic field. The thermal total magnetizations and total magnetic susceptibilities of core/shell Ni/Au are computed. The critical temperature is deduced. The exchange interaction between Ni and Au atoms is obtained. In addition, the total magnetizations versus the external magnetic field and crystal filed for different temperature are also established. © 2013 Elsevier B.V. All rights reserved.


Masrour R.,App Quality | Masrour R.,Mohammed V University | Jabar A.,Mohammed V University | Benyoussef A.,Mohammed V University | And 3 more authors.
Journal of Magnetism and Magnetic Materials | Year: 2015

The magnetic properties of spins-S and σ Ising model on the Bethe lattice have been investigated by using the Monte Carlo simulation. The thermal total magnetization and magnetization of spins S and σ with the different exchange interactions, different external magnetic field and different temperatures have been studied. The critical temperature and compensation temperature have been deduced. The magnetic hysteresis cycle of Ising ferrimagnetic system on the Bethe lattice has been deduced for different values of exchange interactions between the spins S and σ, for different values of crystal field and for different sizes. The magnetic coercive filed has been deduced. © 2015 Elsevier B.V. All rights reserved.


Masrour R.,App Quality | Masrour R.,Mohammed V University | Hlil E.K.,CNRS Neel Institute | Hamedoun M.,Institute of Nanomaterials and Nanotechnologies | And 3 more authors.
Computational Materials Science | Year: 2014

The magnetic properties and electronic structures and of GdBi are reviewed in this manuscript. Self-consistent ab initio calculations, based on DFT (Density Functional Theory) approach and using FLAPW (Full potential Linear Augmented Plane Wave) method within GGA + U approximation, are performed to investigate both electronic and magnetic properties of the GdBi. Polarized spin and spin-orbit coupling are included in calculations within the framework of the antiferromagnetic state between Gd atoms in GdBi with face-centered cubic (fcc) structure. Magnetic moment considered to lie along (1 1 1) axes are computed. Obtained data from ab initio calculations are used as input for the high temperature series expansions (HTSEs) calculations to compute other magnetic parameters. The exchanges interactions J1(Gd-Gd) and J 2(Gd-Gd) between the magnetic atoms are obtained using the mean field theory. The high temperature series expansions (HTSEs) of the magnetic susceptibility of GdBi antiferromagnetic moment (mGd) through GdBi is given up to tenth order series versus of (JGd-Gd/kBT). The Néel temperature TN is obtained by HTSEs of the magnetic susceptibility series using the Padé approximant method. © 2013 Elsevier B.V. All rights reserved.


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 | Year: 2013

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.


Masrour R.,App Quality | Masrour R.,Mohammed V University | Hlil E.K.,CNRS Neel Institute | Hamedoun M.,Institute of Nanomaterials and Nanotechnologies | And 5 more authors.
Journal of Magnetism and Magnetic Materials | Year: 2013

Self-consistent ab initio calculations, based on the density functional theory (DFT) approach and using the full potential linear augmented plane wave (FLAPW) method, are performed to investigate both electronic and magnetic properties of the MnAu layers. Polarized spin and spin-orbit coupling are included in calculations within the framework of the antiferromagnetic state between two adjacent Mn layers. Magnetic moment considered to lie along a axes are computed. The data obtained from the ab initio calculations are then used as input for the high temperature series expansions (HTSEs) calculation to compute other magnetic parameters. The exchange integrals between the magnetic atoms in the same layer and between the magnetic atoms in the bilayers adjacent are given by using mean field theory. The HTSEs of the magnetic susceptibility of MnAu antiferromagnetic spin-S through two model: Ising and XY layers consisting of l=2, 3, 4, 5, 6 and bulk (∞) interacting layers, are studied to sixth order series in β=1/k BT obtained for free-surface boundary conditions. The effects of finite size on critical-point behavior are studied by extrapolation of the high-temperature series. The Néel temperature T N(l) as a function of the number of l spin layers is obtained by HTSEs of the magnetic susceptibility series by using the Padé approximant method and by MFT theory. The critical exponent γ associated with the magnetic susceptibility is deduced. T N(l) for the l-layers are estimated from the divergence of the staggered susceptibility with an exponent for Ising model of γ(1)=2.96, and for XY model of γ(2)=2.82, which is consistent with the basic assumptions of scaling laws. Our estimates for the shift exponent of the Néel temperature for the two models are obtained. © 2012 Elsevier B.V.


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 | Year: 2015

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.


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 | Year: 2015

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.


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 | Year: 2013

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.

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