Abdelkader Boukortt - Academia.edu (original) (raw)

Papers by Abdelkader Boukortt

181-189The structural, electronic and optical properties of GaInAs2 and GaInP2 with chalcopyrite ... more 181-189The structural, electronic and optical properties of GaInAs2 and GaInP2 with chalcopyrite structure in ternaries compounds have been studied in the present paper. To obtain accurate results, we have based our research on three phases. In the first phase, we used the first-principles calculations by using the full potential-linearized augmented plane wave method (FP-LAPW) within the density functional theory (DFT). In the second phase, the structural properties as exchange-correlation potential, the generalized gradient approximation (GGA-PBE Sol) of Perdew and al and local density approximation (LDA) of Perdew and Wang have been used. And in phase three, in order to get best values of the band gap, we used the developed form of GGA proposed by Engel–Vosko (EV-GGA) and the modified Becke-Johnson (mBJ) of Tran and Blaha, which are based on the optimization of total energy and corresponding potential. The compounds of GaInP2 and GaInAs2 demonstrate semiconducting behaviour with ...

Infrared Physics & Technology

Journal of New Technology and Materials, 2018

Optik, 2017

Electronic and optical properties of Na doped zinc oxide (ZnO:Na) were calculated with the FP-LAP... more Electronic and optical properties of Na doped zinc oxide (ZnO:Na) were calculated with the FP-LAPW method by using the LSDA approximations. The lattice constants of ZnO calculated in this study is in a good agreement with experimental and theoretical values. The band gap was increased slightly by doping with Na impurity. Furthermore, we calculated the density of states of Na doped ZnO. The results show that acceptor concentration increases with an increase in Na concentration. Na doping introduces a much shallow acceptor (above the Fermi level), which is of typical p-type behavior. On the other hand, the refractive index, the dielectric function, and the absorption coefficient were determined and show a good agreement with available experimental data. Sodium doping leads to an optical peak at about 395 nm. We found that the intensity of this optical peak increases by the incorporation of Na into ZnO. That peak might improve the optical characteristics of ZnO for solar cell and optical applications.

Chinese Physics B, 2017

The density functional calculation is performed for centrosymmetric (La–Pm) GaO3 rare earth galla... more The density functional calculation is performed for centrosymmetric (La–Pm) GaO3 rare earth gallates, using a full potential linear augmented plane wave method with the LSDA and LSDA exchange correlation to treat highly correlated electrons due to the very localized 4f orbitals of rare earth elements, and explore the influence of U=0.478 Ry on the magnetic phase stability and the densities of states. LSDA calculation shows that the ferromagnetic (FM) state of RGaO3 is energetically more favorable than the anti-ferromagnetic (AFM) one, except for LaGaO3 where the NM state is the lowest in energy. The energy band gaps of RGaO3 are found to be in the range of 3.8–4.0 eV, indicating the semiconductor character with a large gap.

Physica B: Condensed Matter, 2010

We present the results of density functional calculations to study the optical properties of the ... more We present the results of density functional calculations to study the optical properties of the technologically important Zn1−xCdxSySe1−y quaternary alloy, using the full potential linearized augmented plane wave method within the local-density approximation (LDA). Our calculations were performed to evaluate the dielectric function (real and imaginary parts), and the loss function of the II–VI semiconductor alloy. Also the refractive index,

Superlattices and Microstructures, 2009

ABSTRACT RENiAsO compounds have been studied by using density-functional theory with the local sp... more ABSTRACT RENiAsO compounds have been studied by using density-functional theory with the local spin-density approximation (LSDA). In order to take into account the strong on-site Coulomb interaction U present in RENiAsO, we also performed the LSDA+U calculations. We investigated the electronic structure with on-site Coulomb potential for the RE-derived 4f orbitals and Ni-derived 3d to obtain the correct ground state of REFeAsO. The structural parameters, density of states and band structures have been given in detail. Overall, the technique developed and tested in this work holds promise in enabling accurate and fully predictive calculations of strongly correlated electron materials. A detailed analysis shows that the LSDA+U method provides the better description of our systems. No experimental or ab-initio study was related to this series of materials.

physica status solidi (b), 2012

The electronic structure and magnetic behavior of hexagonal rare‐earth diboride RB2 are studied u... more The electronic structure and magnetic behavior of hexagonal rare‐earth diboride RB2 are studied using ab initio density‐functional theory in the DFT + U approach. The effect of the spin–orbit coupling is also investigated and it is found to be a necessary requirement for the accurate description of the magnetic moment. In this paper, we study the magnetic phase stability of RB2 compounds; the band structure and the density of state (DOS) results prove that the coulomb potential and the spin–orbit interaction are keys factors to understand the magnetic properties of these series of materials. In addition, we also explain the behavior of a chemical bond of RB2 compounds through the analysis of the DOS and of the charge density.

Physica B: Condensed Matter, 2012

ABSTRACT The ab initio APW+lo method is used to study the cation effect on the electronic structu... more ABSTRACT The ab initio APW+lo method is used to study the cation effect on the electronic structure of CeBO3 (B=Ga, In) compounds. High-pressure structural behavior, magnetic phase stabilities and electronic properties of both materials have been investigated. The observed most stable phases are the orthorhombic (Pnma) and hexagonal (P63cm) for CeGaO3 and CeInO3, respectively. It is shown that the ferromagnetic (FM) state in CeGaO3 is energetically more favorable than the anti-ferromagnetic (AFM) one, unlike CeInO3 where the AFM-III configuration is the lowest in energy. LSDA+U calculation shows that the valence band maximum is located at T point and the conduction band minimum is located at the center of the Brillouin zone, resulting in a wide indirect energy band gap of about 3.6 eV in the ferromagnetic ordering CeGaO3 which is typical of semiconductor with large gap. CeInO3 compound keeps the metallic character using DFT+U calculation.

Materials Chemistry and Physics, 2010

... a Modelling and Simulation in Materials Science Laboratory, Physics Department, University of... more ... a Modelling and Simulation in Materials Science Laboratory, Physics Department, University of Sidi Bel-Abbes, 22000 Sidi Bel-Abbes, Algeria. b University of Mostaganem, Abdelhamid Ibn Badis, 27000, Algeria. Received 18 ...

physica status solidi (b), 2010

Density functional calculations of Co‐doped ZnO and a theoretical analysis of the optical interba... more Density functional calculations of Co‐doped ZnO and a theoretical analysis of the optical interband transitions are presented. That compound is potentially important for spintronics and magneto‐optoelectronic applications. Using the full potential linearized augmented plane wave (PW) method we analyze the dielectric functions (real and imaginary part) to understand the optical interband transitions. We show that the local spin‐density approximation (LSDA) has severe drawbacks like a spurious Drude‐like peak and a wrong position of the 3d bands which may be repaired by the LSDA + U method. We show the appearance of new peaks in the optical conductivity related with the magnetic impurities which we analyze in detail.

Journal of Physics D: Applied Physics

We present a computational study of the crystal structure and electric polarization of strained w... more We present a computational study of the crystal structure and electric polarization of strained wurtzite III-V nitrides and II-VI oxides, performed in the context of density functional theory and the Berry phase method. The main goal is to investigate the degree to which the lattice parameters, piezoelectric polarization, and piezoelectric constant can be affected by compressive uniaxial strain along the hexagonal c-axis. We show that imposing such strain enhances the piezoelectric response, with both polarization and piezoelectric coefficient increasing from their equilibrium values. The internal parameter of the wurtzite structure also increases with uniaxial strain and eventually becomes equal to 0.5, resulting in a phase transition into the layered hexagonal structure. Furthermore, we discuss the physical origin behind the enhanced piezoelectricity, showing that the enhancement is caused by a strong increase in the response of the internal parameter to strain.

Materials Science in Semiconductor Processing

ECS Journal of Solid State Science and Technology

In this work, we perform first-principles calculations based on density functional theory and the... more In this work, we perform first-principles calculations based on density functional theory and the semi-classical Boltzmann method to study the structural, mechanical, electronic, and thermoelectric properties of rare earths filled skutterudites RECo4Sb12 (RE= Nd,Sm,Eu,Yb). It is found that these compounds are n-type semiconductors with high effective mass and narrow bandgap. The main focus here is to investigate the effect of filler rare earth elements on the thermoelectric response of binary skutterudite CoSb3. In doing so, we compute for each compound the Seebeck coefficient, electrical conductivity, electronic thermal conductivity, and figure of merit in the temperature range from 400 K to 1000 K. The relaxation time and lattice thermal conductivity are calculated as well. Our results reveal that low thermal conductivity and high Seebeck coefficient can be achieved at the same time in RE-filled skutterudites RECo4Sb12, thereby improving their thermoelectric performance which make...

Transactions on Electrical and Electronic Materials

For the sake of reducing the size of the power converters for photovoltaic applications, the micr... more For the sake of reducing the size of the power converters for photovoltaic applications, the microelectronics industry knows a permanent race in order to reach out to integrated electronic components with high efficacy and low losses for different applications. This paper presents a detailed study for designing an integrated structure with a dual-layer inductor model associated with two layers of MPP Molypermaloy magnetic cores. This inductor is intended to a DC–DC boost converter for photovoltaic application purposes. With an input of 17 V, 220 V output and supports a maximum current of 7 A on an operating frequency of 500 kHz with an output ripple less than 0.8%. The research covered the impact of coil's conductor thickness on the inductance. The gap effect study reached to determine the optimum gap between coils permit for the better profiteering of the mutual inductance with low losses. The transmission lines method was used to determine the equivalent electrical circuit for the designed dual-layer inductor to investigate the losses due to the parasite-flowing currents, also, to validate the performance and the well operating of the inductor in the application. The study investigated the magnetic behaviour and current density in conductors by numerical simulation governed by Maxwell's equations and solved by finite element method. An algorithm has been associated with the converter to compensate all losses and ensure the stability of the output voltage. The designed inductor has an inductance of 14.2 µH and covering a volume of 10mm×10mm×2.07mm\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$10\;{\text{mm}} \times 10\;{\text{mm}} \times 2.07\;{\text{mm}}$$\end{document}.

International Journal of Renewable Energy Development

This work aims to optimize the economic dispatch problem of a microgrid system in order to cover ... more This work aims to optimize the economic dispatch problem of a microgrid system in order to cover the load of a commercial building in Algeria. The analyzed microgrid system is connected to the power grid and composed of photovoltaic panels (PV), wind turbine, battery energy storage system (BESS) and diesel generator. To ensure energy balance and the flow of energy, we have implemented an energy management strategy based on Marine Predator Algorithm (MPA) and Multilayer Perceptron Neural Network (MLPNN), which guarantee an optimal economic operation of the system. First, using historical meteorological data, the power generation is forecasted a day-ahead using MLPNN, which allows the optimization of the microgrid operation. Second, the proposed strategy has been studied under three different microgrid configurations. Eventually, the performances of MPA are compared against well-known algorithms. The results indicate that the integration of the PV-BESS microgrid system significantly r...

Philosophical Magazine

ABSTRACT In the present work, we employed the DFT (Density Functional Theory) to investigate the ... more ABSTRACT In the present work, we employed the DFT (Density Functional Theory) to investigate the electronic and magnetic properties of Ni2MnGa Heusler alloy. We focused on the structural transition between tetragonal and cubic structures related to the band Jahn Teller effect. The structural electronic and magnetic properties are calculated for cubic and tetragonally distorted structures. According to the optimisation of total energy versus volume, the tetragonal phase is the ground state for Ni2MnGa alloy 0 K. The band structure and density of state calculations show the ferromagnetic (FM) behaviour, with a total magnetic moment of 4.053 µB and 19.21% of spin polarisation at the Fermi level. Ni2MnGa is a cubic compound above 276 K under a thermal effect, where it gets its shape memory behaviour. Applying uniaxial stress according to the z axis, the studied alloy undergoes a phase transition to the parent phase (cubic) at a pressure around 2.8 GPa. Ni2MnGa alloy has the double possibility of phase transition under thermal effect and uniaxial stress.

Materials Today Communications, 2022

Indian Journal of Pure & Applied Physics, 2015

The structural, electronic and optical properties of GaInAs 2 and GaInP 2 with chalcopyrite struc... more The structural, electronic and optical properties of GaInAs 2 and GaInP 2 with chalcopyrite structure in ternaries compounds have been studied in the present paper. To obtain accurate results, we have based our research on three phases. In the first phase, we used the first-principles calculations by using the full potential-linearized augmented plane wave method (FP-LAPW) within the density functional theory (DFT). In the second phase, the structural properties as exchange-correlation potential, the generalized gradient approximation (GGA-PBE Sol) of Perdew and al and local density approximation (LDA) of Perdew and Wang have been used. And in phase three, in order to get best values of the band gap, we used the developed form of GGA proposed by Engel–Vosko (EV-GGA) and the modified Becke-Johnson (mBJ) of Tran and Blaha, which are based on the optimization of total energy and corresponding potential. The compounds of GaInP 2 and GaInAs 2 demonstrate semiconducting behaviour with the...