| 1. |
- Benhouria, Y., et al.
(author)
-
Quantum Monte Carlo study of dynamic magnetic properties of nano-graphene
- 2018
-
In: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 460, s. 223-228
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Journal article (peer-reviewed)abstract
- Using the Quantum Monte Carlo simulation (QMCS), the dynamic blocking temperature of a nanographene bilayer has been investigated within the framework of the Transverse Ising Model (TIM) with mixed spins, under the existence of the time-dependent oscillating longitudinal magnetic field (h(t) = h(b) + h(0)cos(omega t)) and the transverse field (Omega). The influence of the time-dependent oscillating longitudinal magnetic field, the period of magnetic field (tau) and the transverse field (Omega) on the thermal behavior of the total longitudinal and transverse dynamic order parameters, the total dynamic magnetic susceptibility and the dynamic hysteresis of the nano-graphene bilayer are also studied. As results, we remark the appearance of multiple hysteresis loops and the system exhibits the superparamagnetic behavior at the dynamic blocking temperature.
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| 2. |
- Bouziani, I., et al.
(author)
-
Ab initio study of electronic and optical properties of penta-SiC2 and-SiGeC4 monolayers for solar energy conversion
- 2020
-
In: Superlattices and Microstructures. - : ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD. - 0749-6036 .- 1096-3677. ; 142
-
Journal article (peer-reviewed)abstract
- In the current study, we explore theoretically electronic and optical properties of penta-SiC2 and -SiGeC4 monolayers based on ab initio computations and utilizing modified Becke-Johnson generalized gradient-approximation (mBJ-GGA) within the density functional theory. The calculated results show that both 2D penta-SiC2 and -SiGeC4 are structurally stable, according to their negative formation energy. Furthermore, we have found that the penta-SiC2 and -SiGeC4 semiconductors show indirect and moderate band gaps of 1.75 and 1.62 eV by employing mBJGGA functional, respectively. Also, these systems present sigma- and pi-bond between two nearest neighbor carbon atoms by overlapping sp(2)-sp(2) and p-p orbitals, respectively, as well as an ionic bond between two nearest neighbor Si-C and Ge-C atoms. Additionally, we have shown that the considered compounds exhibit small reflectivity and high absorption peaks in visible region with the shift of absorption edge of 2D penta-SiGeC4 to the low energy visible region due to its small band gap compared to that of 2D penta-SiC2. These findings make both penta-SiC2 and -SiGeC4 monolayer semiconductors promising candidates for photovoltaic technology.
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| 3. |
- Bouziani, I., et al.
(author)
-
Electronic, optical and thermoelectric properties of two-dimensional pentagonal SiGeC4 nanosheet for photovoltaic applications : First-principles calculations
- 2021
-
In: Superlattices and Microstructures. - : Elsevier. - 0749-6036 .- 1096-3677. ; 158
-
Journal article (peer-reviewed)abstract
- In this theoretical study, based on the density functional theory, we investigate the electronic, optical and thermoelectric properties of SiGeC4 nanosheet, within the framework of mBJ-GGA approximation (modified Becke-Johnson generalized gradient approximation). The calculated results indicate that the two-dimensional SiGeC4 compound is energetically, dynamically, thermally and mechanically stable in the pentagonal structure and shows semiconductor character with indirect and moderate bandgap. Also, it is found that this two-dimensional system presents high absorption and low reflectivity as well as high photoconductivity in the visible range. Furthermore, it is shown that the studied compound exhibits good thermoelectric performance with high electrical conductivity and Seebeck coefficient. These results render the twodimensional pentagonal SiGeC4 nanosheet as strong absorber layer candidate in the next generation of photovoltaic devices.
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| 4. |
- Bouziani, I, et al.
(author)
-
Half metallic ferromagnetic behavior in (Ga, Cr)N and (Ga, Cr, V)N compounds for spintronic technologies : Ab initio and Monte Carlo methods
- 2019
-
In: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 477, s. 220-225
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Journal article (peer-reviewed)abstract
- In this article, we investigate the magnetic and electronic properties of GaN doped with simple and double impurities utilizing Ab initio and Monte Carlo studies. We have predicted that (Ga, Cr)N and (Ga, Cr, V)N compounds exhibit ferromagnetic- and halfmetallic-behavior with 100% spin polarization at the Fermi level. Moreover, we have found that Ga1-xCrxN and Ga1-2xCrxVxN (x = 0.04, 0.05 and 0.06) show a second order ferromagnetic transition and that their T-c is above room temperature. These predictions make (Ga, Cr)N and (Ga, Cr, V)N compounds strong candidates for spintronic technologies.
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| 5. |
- Bouziani, I, et al.
(author)
-
High Curie temperature in halfmetallic ferromagnets (Zn, Cr, Ti)Se and (Zn, Cr, Ti)Te for spintronic devices : Ab initio and Monte Carlo treatments
- 2020
-
In: Materials Science & Engineering. - : ELSEVIER. - 0921-5107 .- 1873-4944. ; 253
-
Journal article (peer-reviewed)abstract
- The current study is purposed to investigate the magnetic- and electronic-properties of Zn1-2xCrxTixSe and Zn1-2xCrxTixTe systems by means of Ab initio and Monte Carlo calculations. We have predicted that the two systems show ferromagnetic halfmetallic behavior with 100% spin polarization at the Fermi level and their ferromagnetic stability is attributed to the double exchange coupling. Our calculations suggest further that these compounds exhibit a 2nd order ferromagnetic transition with high Curie temperature. Thus, (Zn, Cr, Ti)Se and (Zn, Cr, Ti)Te compounds are strong candidates for spintronic devices, especially for magnetic random access memories (MRAM) based on the spin transfer torque.
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| 6. |
- Bouziani, I., et al.
(author)
-
Magnetoelectronic properties of GaN codoped with (V, Mn) impurities for spintronic devices : Ab-initio and Monte Carlo studies
- 2018
-
In: Physica A. - : ELSEVIER SCIENCE BV. - 0378-4371 .- 1873-2119. ; 512, s. 1249-1259
-
Journal article (peer-reviewed)abstract
- In this work, we investigate the Magnetoelectronic properties of (V, Mn) codoped GaN using first principles calculations (FPCs) for the spintronic applications. We have obtained the ferromagnetic behavior in (Ga, V)N codoped with Mn atoms, which is believed to be caused by the double exchange mechanism. Moreover, it is observed that our system is halfmetallic at the Fermi level, with 100% spin polarization. The total magnetic moment of (V, Mn) codoped GaN is mainly originated from the V and Mn atoms, and the magnetic moment of V impurities rises with the concentration of V atoms while keeping constant that of the Mn atoms. In addition to that, the exchange coupling is obtained from FPCs and using the Ising model. The Monte Carlo method founded on the Heat Bath algorithm support our FPCs, by investigating the influence of the addition of Mn impurities to (Ga, V)N compound on the critical temperature T-C(MC), the magnetization per site M, the magnetic susceptibility chi and the specific heat C-V. We have found that T-C(MC) is above room temperature as well as the stability of the ferromagnetic state in (Ga, V)N becomes more important after the inclusion of the Manganese.
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| 7. |
- Bouziani, I., et al.
(author)
-
Magnetoelectronic properties of Vanadium impurities co-doped (Cd, Cr)Te compound for spintronic devices : First principles calculations and Monte Carlo simulation
- 2018
-
In: Journal of Magnetism and Magnetic Materials. - : ELSEVIER SCIENCE BV. - 0304-8853 .- 1873-4766. ; 466, s. 420-429
-
Journal article (peer-reviewed)abstract
- We have applied the first-principles calculations to investigate magnetoelectronic properties of Vanadium impurities co-doped (Cd, Cr)Te compound for spintronic devices. The ferromagnetic (FM) nature in (Cd, Cr)Te compound co-doped with V atoms has been found, and the mechanism responsible for this behavior has been considered to be the double exchange. Moreover, the Curie-temperature calculation reveals that the stability's field of the FM-phase rises with rising both the concentration of Cr and V atoms above ambient temperature. This system presents the half-metallic character where its polarization of spin is total at the Fermi level, and its total magnetic moment is principally induced by Cr and V elements. The spin-orbit coupling (SOC) typically play an important role in the electronic structure calculations due to both the concentration of Cr and V impurities. In addition to that, our results have been confirmed by the calculation of magnetization and susceptibility using the Monte Carlo simulation.
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| 8. |
- Bouziani, I., et al.
(author)
-
Two-dimensional Janus Sn2SSe and SnGeS2 semiconductors as strong absorber candidates for photovoltaic solar cells : First principles computations
- 2021
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier. - 1386-9477 .- 1873-1759. ; 134
-
Journal article (peer-reviewed)abstract
- Two-dimensional materials provide new opportunities for the next generation of effective and ultrathin photovoltaic solar cells. Herein, we propose Janus monolayers of Tin monochalcogenides, especially Janus Sn2SSe (type TA) and SnGeS2 (type TB) nanosheets, as strong absorber candidates for solar energy conversion, referring to their excellent electronic and optical properties. Interestingly, based on the first-principles computations, both Janus Sn2SSe and SnGeS2 monolayers possess semiconductor character with indirect and moderate band gaps of 1.60 and 1.61 eV, respectively. Accordingly, the considered systems, Sn2SSe and SnGeS2 single-layers, have high absorption coefficient, reaching up to 49.7 and 62.5 mu m(-1), high optical conductivity of about 4513 and 3559 Omega(-1)cm(-1), as well as low reflectivity never exceed 34.6 and 38.5 % in visible region, respectively. Additionally, the maximum photovoltaic efficiency of single-junction solar cells based on SnGeS2 and Sn2SSe nanosheets can reach as high as 27.47 % and 28.12 %, respectively. The present outstanding results would motivate both theoretical and experimental researchers to deepen the study of the potential applications of twodimensional Janus materials based on Tin monochalcogenides in solar cell technology.
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| 9. |
- Chafai, A., et al.
(author)
-
First-principles insights into the optical and electronic characteristics of barium intercalated AB-stacked bilayer graphene
- 2023
-
In: The European Physical Journal Plus. - : Springer Nature. - 2190-5444. ; 138:8
-
Journal article (peer-reviewed)abstract
- The present study describes the electronic and optical characteristics of barium atoms (an alkaline earth metal) intercalated within AB-stacked bilayer graphene (AB-2LG). Using state-of-the-art first-principles computations and taking into account the dispersion forces between the diverse nanosheets, we determined that the intercalation of barium atoms (Ba) into AB-2LG increases the interlayer distance from 3.357 to 5.584 degrees A, and no C-Ba bond formation has been observed. In addition, our findings reveal that the presence of Ba atoms inside the AB-2LG induces a change in the Space group number from 164 (pure AB-2LG) to 156 (Ba-intercalated AB-2LG). Concurrently, we observed that the AB-2LG band structure exhibits a Dirac cone at the K-point, which is a characteristic signature of a semi-metallic character. By contrast, the electronic behavior of the barium-intercaled AB-2LG is found to be metallic. Also, we noticed that the confinement of Ba atoms into the AB-2LG shifts the Dirac point under the Fermi level. Additionally, upon examining the optical properties under the 001 and 100-polarization of the incident light, we found that all optical parameters of both under-investigated bidimensional materials exhibit an anisotropic character. Interestingly, under the 001-polarization, we observed that the intercalation of AB-2LG with Ba atoms reduces the optical absorption to zero in the visible region, and blueshifts are the absorption peak observed in the infrared region. Furthermore, in the case of 001-polarization, the presence of Ba atoms enhances the optical absorption in the 7-9 eV spectral range. However, the obtained data exhibit a remarkable decrease in the refractive index after the Ba intercalation process, for both considered polarization directions.
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| 10. |
- Haman, Z., et al.
(author)
-
Structural, electronic and optical properties of two-dimensional Janus transition metal oxides MXO (M = Ti, Hf and Zr; X = S and Se) for photovoltaic and opto-electronic applications
- 2021
-
In: Physica. B, Condensed matter. - : Elsevier. - 0921-4526 .- 1873-2135. ; 604
-
Journal article (peer-reviewed)abstract
- Two-dimensional Janus transition metal dichalcogenides structures have drawn increasing importance due to their remarkable properties for versatile applications in optoelectronic, photo-catalytic, thermo-electricity, piezoelectricity and spintronic. In this Paper, by employing the Ab-initio computations based on the density functional theory, the structural, electronic and optical properties of Janus MXO (M = Ti, Hf and Zr; X = S and Se) mono-layers are investigated utilizing full potential linearized augmented plane waves (FP-LAPW) method. The lattice parameters of the six Janus were computed, which are close to the previous theoretical results. The density of states and the electronic band structures were investigated for the first time using (GGA-PBE) approximation for the potential of the exchange and correlation. The optical parameters like complex dielectric function, refractive index, reflectivity, extinction and absorption coefficients of all Janus were performed. Our results reveal strong absorption coefficient and low reflectivity in the visible and ultraviolet regions, which make them candidates for opto-electronic and photovoltaic applications.
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| 11. |
- Kibbou, M., et al.
(author)
-
Cs2InGaX6 (X=Cl, Br, or I) : Emergent Inorganic Halide Double Perovskites with enhanced optoelectronic characteristics
- 2021
-
In: Current applied physics. - : Elsevier BV. - 1567-1739 .- 1878-1675. ; 21, s. 50-57
-
Journal article (peer-reviewed)abstract
- During the last decade, Inorganic Halide Double Perovskite materials have attracted widespread interest as a promising eco-friendly and non-toxic alternative to lead based hybrid halide organic–inorganic perovskites materials, with outstanding Stability, Structural and electronic properties. In this study, First-Principles density functional theory (DFT) calculations were performed on the structural, stability, electronic and optical properties of the transition metal-based double perovskites materials Cs2InGaX6 (X = Cl, Br, or I). Our results reveal that all these materials exhibit excellent thermodynamic and structural stability owing to their negative formation energies and Goldsmith's factors. It is also observed that Cs2InGaCl6, Cs2InGaBr6, and Cs2InGaI6 materials exhibit band gaps calculated by different functional (GGA-PBE and TB-mpj) in visible-range between 0.89 and 3.24 eV. Furthermore, the computed optical properties reveal strong absorption in UV, visible, and IR range with high optical conductivity and low reflectivity. These obtained results predict that the three transition metal-based double perovskites materials carries promising application in nano-electronic and optoelectronic device applications and can be considered as photovoltaic absorber materials.
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| 12. |
- Behloul, M., et al.
(author)
-
Electronic and magnetic behaviors of (V, Mn), (V, Fe) and (V, Cu) codoped tin carbide : Ab initio and Monte Carlo calculations
- 2022
-
In: Materials Today. - : Elsevier. - 2214-7853. ; , s. 448-453
-
Conference paper (peer-reviewed)abstract
- In the present study, we performed ab initio calculations for tin carbide codoped with (V,Mn), (V,Cu) and (V,Fe). The electronic and magnetic properties of tin carbide are calculated by means of density functional theory (DFT). The half metallic ferromagnetic behaviour of dual impurities VMnSnC, VFeSnC and VCuSnC is treated by using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA). Our results evince that, the stability of ferromagnetism state was induced by the charge state of magnetic impurities, which room temperature ferromagnetic DMS based spintonic is realized. The exchange interactions are obtained from first principles calculations using an Ising model. Our calculation is supported by Monte Carlo simulation based on the heat bath algorithm. We have examined the effects of magnetic parameters for magnetization, internal energy and magnetic susceptibility.
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| 13. |
- Behloul, M., et al.
(author)
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Ferromagnetism induced by Cr, V single and double impurities doped BN from Ab-initio and Monte Carlo study
- 2018
-
In: COMPUTATIONAL CONDENSED MATTER. - : ELSEVIER SCIENCE BV. - 2352-2143. ; 16
-
Journal article (peer-reviewed)abstract
- Using the Ab initio calculations and Monte Carlo (MC) simulations, we investigate the electronic and magnetic properties of cubic BN compound doped and co-doped with Chromium (Cr) and Vanadium (V) atoms. The calculated electronic band structure and density of states (DOS) of doped BN with single and double impurities can induce localized edge states around Fermi level, leading from semiconductor to half-metal transition. Thereafter, the stability of ferromagnetic (FM) ordering and disordered local magnetic moment (DLM) configurations has been explored. The interesting Curie temperature (T-c), magnetization and susceptibility results for the various concentrations of Chromium (Cr) and Vanadium (V) co-doped (doped) BN suggest a vast exploitation attention in spintronic applications.
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| 14. |
- Behloul, M., et al.
(author)
-
Theoretical investigation of the electronic and magnetic properties of Zn (Fe, Co) Se : Ab initio calculations and Monte Carlo simulations
- 2019
-
In: Superlattices and Microstructures. - : ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD. - 0749-6036 .- 1096-3677. ; 127, s. 66-70
-
Journal article (peer-reviewed)abstract
- On the basis of spin density functional calculation, the electronic and magnetic properties of ZnSe doped with double impurities Zn1-2xFexCoxSe (x = 0.05) are studied using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) method within the local density approximation (LDA). The half-metallic ferromagnetic nature of (Fe, Co) doped ZnSe is investigated. Therefore the electronic structure and magnetic properties of Zn1-2xFexCoxSe exhibit a half-metallic ferromagnetic character; the stability of ferromagnetic (FM) compared to the disorder local moment (DLM) has been discussed. Our calculation is supported by Monte Carlo simulations (MCS) based on the heat bath algorithm. We have examined the effects of system size L on magnetization, specific heat and magnetic susceptibility. The spin density functional calculation results are in good agreement with the literature, especially for 5% of (Co, Fe) each, which gives the most interesting results.
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| 15. |
- Benhouria, Y., et al.
(author)
-
Carbides-anti-perovskites Mn3(Sn, Zn)C : Potential candidates for an application in magnetic refrigeration
- 2020
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 124
-
Journal article (peer-reviewed)abstract
- In the present study, the combination of the First-principles density functional theory (DFT) calculations and Monte Carlo (MC) methods are investigated on the structural, magneto-electronic and magneto-caloric properties of the anti-perovskite carbides Mn3XC with X = Sn, Zn. Firstly, the electronic band structure and total/partial density of state of both Mn3SnC and Mn3ZnC are computed and compared to other theoretical and experimental works. Our results reveal that both Mn3SnC and Mn3ZnC structures exhibit a metallic behavior and the valence (VB) and conduction (CB) bands overlap considerably. Additionally, the magnetic and magneto-caloric properties including heat capacity (C), the entropy change (ΔS), adiabatic temperature (ΔT) and the refrigerant capacity (RC) were studied under the magnetic field ranging between 0 and 5 T for both anti-perovskites. Our findings suggest that both anti-perovskite carbide (Mn3SnC and Mn3ZnC) can act as an effective substrate for magnetic refrigeration.
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| 16. |
- Benhouria, Y., et al.
(author)
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Dielectric Properties and Hysteresis Loops of a Ferroelectric Nanoparticle System Described by the Transverse Ising Model
- 2014
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In: Journal of Superconductivity and Novel Magnetism. - : Springer Science and Business Media LLC. - 1557-1939 .- 1557-1947. ; 27:9, s. 2153-2162
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Journal article (peer-reviewed)abstract
- In this work, we use the effective field theory based on the probability distribution method to investigate the longitudinal and transverse polarizations, susceptibility, pyroelectric coefficient, and the hysteresis behavior of a ferroelectric cubic nanowire. The effects of the core-shell exchange interaction and the core-shell transverse fields on the longitudinal and transverse polarizations, the susceptibility, the pyroelectric coefficient, and the hysteresis loops of the system are examined. Some characteristic phenomena are found in the thermal variations, depending on the physical parameters in the shell and in the core.
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| 17. |
- Benhouria, Y., et al.
(author)
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Dynamic Magnetic Properties of a Mixed Spin Ising Double-Walled Ferromagnetic Nanotubes : A Dynamic Monte Carlo Study
- 2017
-
In: Journal of Superconductivity and Novel Magnetism. - : Springer Science and Business Media LLC. - 1557-1939 .- 1557-1947. ; 30:3, s. 839-844
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Journal article (peer-reviewed)abstract
- Using the dynamic Monte Carlo simulation, the dynamic critical temperature of a ferromagnetic or ferrimagnetic double-walled nanotubes (DWNTs) is studied within the kinetic Ising model under the presence of a time-dependent oscillating external magnetic and crystal fields with mixed spins S (A) = 1 and S (B) = 3/2. The effects of the time-dependent oscillating external magnetic field, the period of the oscillating magnetic field, and the crystal field on the thermal behavior of the dynamic sub-lattice order parameters and the total dynamic order parameter, total dynamical magnetic susceptibility, dynamical specific heat, and dynamic hysteresis of a DWNTs are studied. Our theoretical predictions may be a reference for future experiment studies of the nanostructures.
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| 18. |
- Benhouria, Y., et al.
(author)
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Dynamic magneto-caloric effect of a C70 fullerene : Dynamic Monte Carlo
- 2019
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 108, s. 191-196
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Journal article (peer-reviewed)abstract
- Using the dynamicMonte Carlo (DMC) simulation, the dynamic magnetocaloric effect of a ferrimagnetic C70 Fullerene-like structure is studied within the dynamic Ising model under of a magnetic (h(t)) field. The influences of the amplitude (h0) and the frequency (ω) of the h(t) magnetic field and bias field (hb) on the thermal behavior of the dynamic order parameter and the dynamic magnetocaloric properties (the dynamic isothermal ΔSiso(T,h(t)) entropy variation and the dynamic ΔTad (T,h(t)) adiabatic variation of temperature), the dynamic specific heat, the dynamic entropy and as well as the dynamic refrigerant capacity (RC(t)) ferrimagnetic C70 Fullerene-like structure are studied. Our results may be a reference for future experiment and theoretical studies of the nano-clusters.
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| 19. |
- Benhouria, Y., et al.
(author)
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Dynamic magneto-caloric effect of a multilayer nanographene : Dynamic quantum Monte Carlo
- 2019
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 105, s. 139-145
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Journal article (peer-reviewed)abstract
- Using the dynamic quantum Monte Carlo simulation, the dynamic magnetocaloric effect of a ferromagnetic multilayer nanographene (MNG) is studied within the dynamic Ising model under the applied of a time-dependent oscillating (h(t)) magnetic field. The influence of the amplitude h(0) and the period tau of the h(t) and the transverse field Omega on the thermal behavior of the dynamic order parameter and the dynamic magnetocaloric properties (the dynamic isothermal Delta S-T (T, h(t)) entropy change and the dynamic Delta T-ad (T, h(t)) adiabatic change of temperature), the dynamic specific heat, the dynamic entropy and as well as the dynamic relative cooling power (RCP(t)) ferrimagnetic MNG are studied. Our predicted results may be a reference for future experiment and theoretical studies of the nanostructures.
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| 20. |
- Benhouria, Y., et al.
(author)
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Examination of the Magnetic Properties of the Triangular Type Mixed spin-(1/2,1) Nanowire
- 2020
-
In: Journal of Superconductivity and Novel Magnetism. - : SPRINGER. - 1557-1939 .- 1557-1947. ; 33:3, s. 817-824
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Journal article (peer-reviewed)abstract
- In the presence of the crystal field D/J(Core) and the external magnetic field h/J(Core), using the Monte Carlo (MC) simulation based on the heat bath algorithm and the effective field theory (EFT), the triangular mixed spin nanowire model consisting of a spin-(1/2) core which is encircled by a spin-1 ferrimagnetic surface shell is studied. We have studied the special effects of the core surface and crystal field on the critical and compensation temperatures. Several properties, such as the magnetization, hysteresis behaviors, coercive field, and remanent magnetizations are studied. For the appropriate values of the system parameters, the compensation point and multi-loops are found PACS 05.50. + q; 77.80. Bh.
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| 21. |
- Benhouria, Y., et al.
(author)
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Hysteresis Behavior and Pyroelectric Properties of Multi-Surface Ferroelectric Thin Films
- 2015
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In: Zhongguó wùli xuékan. - 0577-9073. ; 53:4
-
Journal article (peer-reviewed)abstract
- Using the transverse Ising model, we investigate the dielectric properties and the hysteresis behavior of multi-surface ferroelectric (MSF) thin films in the framework of the effective field theory based on the probability distribution technique that accounts for the self-spin correlation functions. The effects of the exchange interactions and the transverse field on the longitudinal and the transverse polarizations, the dielectric susceptibility, the pyroelectric coefficient, and the hysteresis loops are studied. A number of interesting phenomena have been found.
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| 22. |
- Benhouria, Y., et al.
(author)
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Hysteresis loops and dielectric properties of a mixed spin Blume-Capel Ising ferroelectric nanowire
- 2018
-
In: Physica A. - : ELSEVIER SCIENCE BV. - 0378-4371 .- 1873-2119. ; 506, s. 499-506
-
Journal article (peer-reviewed)abstract
- The critical and hysteresis behaviors of a ferrielectric Blume-Capel nanowire are studied using the 'sing model with mixed spins -(1/2,1) in the presence of both an external longitudinal electric (E-z) and crystal anisotropy (D) fields. We use the Monte Carlo simulations (MCs) to examine the influence of E-z, D and the exchange interactions on the compensation and critical temperatures, the specific heat, the dielectric susceptibility and the internal energy of the system. Our theoretical predictions are in accordance with some experimental and theoretical results.
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| 23. |
- Benhouria, Y., et al.
(author)
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Hysteresis loops and dielectric properties of compositionally graded (Ba,Sr)TiO3 thin films described by the transverse Ising model
- 2016
-
In: Zhongguó wùli xuékan. - : Elsevier BV. - 0577-9073. ; 54:4, s. 533-544
-
Journal article (peer-reviewed)abstract
- Using the effective field theory with a probability distribution technique that accounts for the self-spin correlations, we apply the transverse spin-1/2 Ising model to study the intrinsic hysteresis of compositionally graded Ba1-xSrxTiO3 (BST) thin films with x decreasing from 0.20 to 0.10 in successive slabs. The random bond model of related parameters is applied to mimic doping. The effects of the thickness, the concentration of Sr, the number of slabs and the temperature on the polarization and the hysteresis are discussed.
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| 24. |
- Benhouria, Y., et al.
(author)
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Monte Carlo simulation of dielectric properties of a mixed spin-3/2 and spin-5/2 Ising ferrielectric nanowires
- 2017
-
In: Ferroelectrics (Print). - : TAYLOR & FRANCIS LTD. - 0015-0193 .- 1563-5112. ; 507:1, s. 58-68
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Journal article (peer-reviewed)abstract
- Dielectric properties of Ising ferrielectric nanowires with spin-3/2 core and spin-5/2 shell structure are systematically studied by the use of the Monte Carlo simulation in the presence of the external longitudinal electric field. Special focus is given to the effects of the core and shell interactions, the interface coupling and the temperature on the core and shell polarizations, the specific heat, the compensations points, the susceptibility and hysteresis behaviors. Some characteristic behaviors are found, such as the existence of triple hysteresis loops for appropriate values of the system parameters affected by the antiferroelectric interface coupling constant and the temperature. The results are compared with those of recently published works and a qualitatively good agreement is found.
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| 25. |
- Benhouria, Y., et al.
(author)
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Monte Carlo Study of Long-Range Interactions of a Ferroelectric Bilayer with Antiferroelectric Interfacial Coupling
- 2013
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In: Journal of Superconductivity and Novel Magnetism. - : Springer Science and Business Media LLC. - 1557-1939 .- 1557-1947. ; 26:10, s. 3075-3083
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Journal article (peer-reviewed)abstract
- By the use of Monte Carlo simulation, we have studied the critical behavior of a ferroelectric bilayer with antiferroelectric interfacial coupling using the transverse spin- Ising model. We discuss the effects of long-range interactions for the internal energy, specific heat, free energy, dielectric susceptibility, and polarization. The dependence of the Curie temperature on the thickness of the bilayer, long-range interactions, and the transverse field was also investigated. It is assumed that the long-range interaction decays with the distance between the pseudo-spins as a power law.
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| 26. |
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| 27. |
- Benhouria, Y., et al.
(author)
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Thermodynamic properties and hysteresis behaviors of a mixed spin-3/2 and spin-1/2 Ising double walled ferrielectric nanotubes : A Monte Carlo study
- 2014
-
In: Superlattices and Microstructures. - : Elsevier BV. - 0749-6036 .- 1096-3677. ; 75, s. 761-774
-
Journal article (peer-reviewed)abstract
- The hysteresis loops and the thermodynamic properties of a ferroelectric or ferrielectric double walled nanotubes (A and B) are studied within the Ising model with mixed spins (S-A = 3/2 and S-B = 1/2) in the presence of the crystal and the external longitudinal electric fields. We use the Monte Carlo method to investigate the effects of the external electric field, the crystal field and the exchange interactions on the total polarization, susceptibility, specific heat and the internal energy of a double walled nanotubes (DWNTs).
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| 28. |
- Bouhou, S., et al.
(author)
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Investigation of a core/shell Ising nanoparticle : Thermal and magnetic properties
- 2016
-
In: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 481, s. 124-132
-
Journal article (peer-reviewed)abstract
- The phase diagrams and magnetic hysteresis behavior of a spin-1/2 Ising core/shell nanoparticle are investigated by the use of the effective field theory with a probability distribution technique that accounts for the self-spin correlation functions. Nearest-neighbor pair interactions are incorporated between the Ising spins in the three parts of the nanoparticle that are core, core/shell and surface shell. The effects of the external magnetic field and core/shell exchange interaction on the thermal magnetization and susceptibility of the system are examined.
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| 29. |
- Bouhou, S., et al.
(author)
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Magnetic properties of a single transverse Ising ferrimagnetic nanoparticle
- 2015
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In: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 456, s. 142-150
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Journal article (peer-reviewed)abstract
- Using the effective field theory with a probability distribution technique that accounts for the self-spin correlation function, the thermal and the magnetic properties of a single Ising nanoparticle consisting of a ferromagnetic core, a ferromagnetic surface shell and a ferrimagnetic interface coupling are examined. The effect of the transverse held in the surface shell, the exchange interactions between core/shell and in surface shell on the free energy, thermal magnetization, specific heat and susceptibility are studied. A number of interesting phenomena have been found such as the existence of the compensation phenomenon and the magnetization profiles exhibit P-type, N-type and Q-type behaviors. (C) 2014 Elsevier B.V. All rights reserved.
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| 30. |
- Bouhou, S., et al.
(author)
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Magnetic Properties of a Transverse Ising Nanoparticle
- 2015
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In: Journal of Superconductivity and Novel Magnetism. - : Springer Science and Business Media LLC. - 1557-1939 .- 1557-1947. ; 28:3, s. 885-890
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Journal article (peer-reviewed)abstract
- We use the effective field theory with a probability distribution technique to investigate the magnetic properties of an antiferromagnetic Ising core/shell nanoparticle with a negative interlayer coupling core/shell in the presence of both the longitudinal and the transverse fields. Nearest-neighbor pair interactions are incorporated between the Ising spins in three parts that are core, core/shell, and surface shell. The effects of the external and the transverse fields and the exchange interactions between core/shell and in surface shell on the hysteresis loops and the susceptibility of the nanoparticle are examined. A number of interesting phenomena have been found.
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| 31. |
- Bouhou, S., et al.
(author)
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Magnetic Properties of Diluted Magnetic Nanowire
- 2013
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In: J SUPERCOND NOV MAGN. - : Springer Science and Business Media LLC. - 1557-1939. ; 26:1, s. 201-211
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Journal article (peer-reviewed)abstract
- A magnetic diluted nanowire with cylindrical structure described by the Ising model is investigated. Using the effective field theory with a probability distribution technique, the influence of the dilution on the phase diagrams, susceptibility and the hysteresis loops are discussed in detail. Novel features are obtained for the thermal variations of longitudinal susceptibility and longitudinal magnetization. We have investigated the magnetic reversal of the system and have found the existence of triple hysteresis loops patterns, affected by the concentration of magnetic atoms, the temperature, and the exchange interaction between the core and the surface shell.
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| 32. |
- Bouhou, S., et al.
(author)
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Phase diagrams of diluted transverse Ising nanowire
- 2013
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In: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 336, s. 75-82
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Journal article (peer-reviewed)abstract
- In this paper, the phase diagrams of diluted Ising nanowire consisting of core and surface shell coupling by J(cs) exchange interaction are studied using the effective field theory with a probability distribution technique, in the presence of transverse fields in the core and in the surface shell. We find a number of characteristic phenomena. In particular, the effect of concentration c of magnetic atoms, the exchange interaction core/shell, the exchange in surface and the transverse fields in core and in surface shell of phase diagrams are investigated.
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| 33. |
- Bouhou, S., et al.
(author)
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Some hysteresis loop features of 2D magnetic spin-1 Ising nanoparticle : shape lattice and single-ion anisotropy effects
- 2017
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In: Zhongguó wùli xuékan. - : Elsevier BV. - 0577-9073. ; 55:6, s. 2224-2235
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Journal article (peer-reviewed)abstract
- The effects of longitudinal and transverse crystal-fields on the magnetic hysteresis behaviors of 2D spin-1 Ising nanoparticles are investigated, by using the effective-field theory based on the probability distribution technique with correlations. Nanoparticles with hexagonal or square lattice are studied. A number of characteristic phenomena such as triple and quadruple hysteresis loop behaviors have been observed for certain physical parameters, originating from the competitions among the core/shell exchange interaction, anisotropies, temperature and the longitudinal magnetic field. Finally, the obtained results are compared with some experimental and theoretical results.
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| 34. |
- Bouziani, I, et al.
(author)
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Electronic and optical properties of ZnO nanosheet doped and codoped with Be and/or Mg for ultraviolet optoelectronic technologies : density functional calculations
- 2020
-
In: Physica Scripta. - : IOP PUBLISHING LTD. - 0031-8949 .- 1402-4896. ; 95:1
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Journal article (peer-reviewed)abstract
- Theoretically, the density functional calculations have been effectuated for investigating electronic and optical properties of zinc oxide nanosheet doped and codoped with Be and/or Mg utilizing the generalized gradient approximation modified Becke-Johnson (GGA-mBJ) approach. The computed results show that the ZnBeO, ZnMgO and ZnBeMgO in nanosheet structure, referring to their low formation energy values, are more stable than those in bulk one. Furthermore, the bandgap of ZnO monolayer can be effectively modulated through substitution of Zn atoms by Be and/or Mg. In addition to that, by incorporating Be and/or Mg, the absorption peaks of ZnO nanosheet shift into the shorter UV-wavelength side as well as its reflectivity becomes lower. These results indicate that doping and codoping process of ZnO monolayer with Be and/or Mg are two efficient ways to modulate electronic and optical properties for ultraviolet optoelectronic technologies.
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| 35. |
- Chafai, A., et al.
(author)
-
Binding energy of an exciton in a GaN/AlN nanodot : Role of size and external electric field
- 2019
-
In: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 559, s. 23-28
-
Journal article (peer-reviewed)abstract
- We report the impact of an external electric field on the energy spectrum of an exciton inside a spherical shaped GaN/AlN core/shell nanodot. The modulation of the confined exciton lowest state energy by the nanodot size is also treated. Our theoretical approach, based on a variational calculation, predicts a remarkable decrease in the exciton's energy when the electric field is switched on. Furthermore, our investigation shows that for a fixed nanodot size, the energy redshift is a unique function of the external electric field strength. On the other hand, it was observed that as the nanodot size increases the lowest exciton energy decreases and vice versa.
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| 36. |
- Chafai, A., et al.
(author)
-
External electric field modulation of single-layer MoSe2 electronic and optical properties : A first-principles investigation
- 2023
-
In: MICRO AND NANOSTRUCTURES. - : Elsevier. - 2773-0123. ; 182
-
Journal article (peer-reviewed)abstract
- A wisely applied external electric field could effectively develop the optoelectronic properties of single-layer materials. The optical and electronic characteristics of monolayer molybdenum diselenide (ML-MoSe2) are deeply studied by means of density functional computations (DFT) to pinpoint the effect of the out-of-plane applied electric field (F//Oz). In fact, variations in the applied electric field strength gradually increase the energy of the electronic band gap (Eg) from 1.44 eV at 0V/& ANGS; to 1.51 eV at & PLUSMN;0.6V/& ANGS;. We also probed a sharp drop in the energy gap at high intensities. However, dielectric function, reflectivity, and loss function are studied for unpolarized and polarized incident light. Interestingly, the 001-polarization of the incident light affects the dielectric function's magnitude and position; this effect is more emphasized in the presence of an electric field with positive strengths. Furthermore, we found that the applied negative/positive electric field enhances the UV-visible reflectivity. Also, blue shifts of the ML-MoSe2 optical properties spectrum appear when subjected to the 001-polarized incident light. However, the loss function exhibits a weak response to the applied F. Additionally, we obtain that the 001-light polarization improves a plasmonic peak around 100 nm. Our results will provide a new view to understanding the controllable optical and electronic properties of MoSe2 monolayer, which is valuable for the design of new optoelectronic and plasmonic devices under development.
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| 37. |
- Chafai, A., et al.
(author)
-
Hydrogenic donor in a CdSe/CdS quantum dot : Effect of electric field strength, nanodot shape and dielectric environment on the energy spectrum
- 2018
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 104, s. 29-35
-
Journal article (peer-reviewed)abstract
- The impact of an external electric field on the binding energy of a single donor impurity was examined within the effective-mass approach by deploying a variational calculation. The discontinuity of the permittivity, epsilon(r), and of the particle effective mass, m(i)*(r), at the nanosystem boundaries was considered. Using the image charge approach, the impact of the surrounding medium on the shallow donor energy spectrum was also taken into account. Our theoretical investigation shows that, for zero electric field and when the shell thickness is taken constant, the increase of the core material size leads to decrease the single donor correlation energy. Further, for a fixed core material size the energy decreases quickly when the shell thickness moves from 0 to 1 nm, while it decreases very slowly when the shell thickness is ranged between 1 nm and 4 nm. On the other hand, we have established that when we turn on an external electric field, the probability density of confined particles tends to move towards the nanodot border which naturally shifts the energy spectrum to lower energies (redshift). It was also obtained that the donor Stark shift depends not only on the nanodot size, but also on the surrounding medium.
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| 38. |
- Chafai, A., et al.
(author)
-
Linear and nonlinear optical properties of donors inside a CdSe/ZnTe core/shell nanodot : Role of size modulation
- 2019
-
In: RESULTS IN PHYSICS. - : ELSEVIER. - 2211-3797. ; 14
-
Journal article (peer-reviewed)abstract
- The optical absorption coefficient (OAC) and the refractive index (RI), related to a confined donor, were theoretically investigated by the mean of the density matrix formalism. In order to obtain the 1s - 1p donor transition energy a variational calculation, within the context of the effective-mass approach, was deployed. Our numerical results exhibit the possibility to modulate the electronic and optical properties of confined donors by tailoring the inner and outer radii of the core/shell heterodot. Further, we have obtained that the nanodot size shrinking leads, for very small values of core radius, to reduce the magnitude of the total absorption coefficient resonance peak. It was also obtained that the resonance peak position of the absorption coefficient is redshifted with increasing the core radius for a fixed shell thickness. The same situation occurs when reducing the thickness of the shell material for a fixed core size.
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| 39. |
- Chafai, A., et al.
(author)
-
Nonlinear optical characteristics of an exciton in a GaSb-capped InSb heterodot : role of size control
- 2020
-
In: The European Physical Journal Plus. - : SPRINGER HEIDELBERG. - 2190-5444. ; 135:2
-
Journal article (peer-reviewed)abstract
- The optical characteristics of a bound electron-hole quasiparticle inside a GaSb-capped InSb nanodot were investigated using a combination between a density-matrix approach and variational calculations. Our theoretical model considers the electric permittivity mismatch between the core and shell materials via the self-energy term obtained by the means of an image charge approach. Furthermore, the core-to-shell conduction and valence band offsets were modeled by finite-depth confinement potentials. To elucidate the impact of the nanoheterodot spatial parameters on the confined exciton optical properties, we have investigated the change of the refractive index, the optical absorption coefficient, and the 1p-1s exciton transition energy with respect to the nanodot shape. Our numerical results exhibit the great potential for the improvement of the exciton optical properties by tailoring the nanodot size. It was also obtained that, for a fixed core radius, the resonance peak position of the optical absorption coefficient was still constant after a certain shell thickness value. Otherwise, decreasing the shell thickness leads to blue-shifting the 1p-1s transition energy.
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| 40. |
- Chafai, A., et al.
(author)
-
Recombination energy for negatively charged excitons inside type-II core/shell spherical quantum dots
- 2018
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : ELSEVIER SCIENCE BV. - 1386-9477 .- 1873-1759. ; 101, s. 125-130
-
Journal article (peer-reviewed)abstract
- The recombination energy of isolated neutral exciton and that of isolated negatively charged exciton inside a type-II core/shell spherical quantum dot are studied. Our investigation considers the charge-carriers effective mass discontinuity at the surface contact between the core and shell materials. Although our model omits the effect of the surface polarization, the dielectric-constant mismatch at the nanodot boundaries was taken into account. In order to achieve the exciton and negative trion energies, we proceed by a variational calculation in the framework of the envelope approximation. Our results reveal a strong correlation between the nanodot morphology and the energy spectrum of the neutral and negatively charged exciton.
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| 41. |
- Chafai, A., et al.
(author)
-
Role of a uniform magnetic field on the energy spectrum of a single donor in a core/shell spherical quantum dot
- 2019
-
In: Zhongguó wùli xuékan. - : ELSEVIER SCIENCE BV. - 0577-9073. ; 57, s. 189-194
-
Journal article (peer-reviewed)abstract
- Using the variational approach within the framework of the effective-mass approximation (EMA), the binding energy of a centred hydrogenic donor impurity in a CdSe/ZnTe core/shell spherical quantum dot (CSSQD) in the presence of an external magnetic field was investigated. In this model, we have taken into account the effect of the radial dependence of the dielectric constant and of the electron effective mass. Our numerical results show a remarkable influence of the nanodot spatial parameters and of the external magnetic field strength on the shallow donor binding energy.
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| 42. |
- Chafai, A., et al.
(author)
-
Shallow donor inside core/shell spherical nanodot : Effect of nanostructure size and dielectric environment on energy spectrum
- 2017
-
In: Superlattices and Microstructures. - : Elsevier BV. - 0749-6036 .- 1096-3677. ; 111, s. 976-982
-
Journal article (peer-reviewed)abstract
- We have reported the impact of the core and shell radii on the energy spectrum of centered shallow donor confined inside CdSe/ZnTe core/shell quantum dot and ZnTe/CdSe inverted core/shell quantum dot. The dielectric discontinuity between the nanosystems and their surrounding medium was considered. In order to examine the behavior of the donor binding energy as a function of the spatial parameters a variational approach within the framework of the effective-mass approximation was deployed. Our model shows that for a fixed shell radius the increase of the core radius value blue-shifts the binding energy of the donor inside inverted core/shell quantum dot only if the value of the core to shell radii ratio is between 0.9 and 1, otherwise it is red-shifted. By contrast, for core/shell quantum dot system the binding energy is red-shifted by increasing the core radius for a fixed nanostructure size and for all values of the core to shell radii ratio. We have also found that the donor binding energy values are more important in a core/shell nanodot than in an inverted core/shell quantum dot.
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| 43. |
- Chafai, A., et al.
(author)
-
Tuning the binding energy of on-center donor in CdSe/ZnTe core/shell quantum dot by spatial parameters and magnetic field strength
- 2017
-
In: Physica. E, Low-Dimensional systems and nanostructures. - : Elsevier BV. - 1386-9477 .- 1873-1759. ; 94, s. 96-99
-
Journal article (peer-reviewed)abstract
- The behavior of the electron ground state and of the ground state binding energy of an on-center donor confined in a CdSe/ZnTe core/shell spherical nanodot was examined theoretically within the framework of the effectivemass approximation and using a variational calculation. The radial dependence of the dielectric constant and of the electron effective mass as well as the effect of the polarization charge were considered. Our results highlight the large impact of the magnetic field strength and the spatial parameters on the energy behavior for both the electron and the donor. Our study points out also the fact that the magnetic confinement may be eclipsed by the spatial confinement in heteronanostructures with small size and expected to be dominant in the opposite case.
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| 44. |
- El Hamri, M., et al.
(author)
-
A theoretical study of the hysteresis behaviors of a transverse spin-1/2 Ising nanocube
- 2016
-
In: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 413, s. 30-38
-
Journal article (peer-reviewed)abstract
- The applied magnetic field dependencies of the surface shell, core and total magnetizations of a transverse spin -I Ising nanocube are investigated within the effective -field theory with correlations, based on the probability distribution technique, for both ferro- and antiferromagnetic exchange interactions. We have found that interfacial coupling has a strong effect on the shape and the number of hysteresis loops and also on the coercive field and remanent magnetization behaviors. Furthermore, when the temperature exceeds a critical one, the coercivities of the core, the surface shell and the system become zero.
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| 45. |
- El Hamri, M., et al.
(author)
-
Hysteresis loop behaviors of a decorated double-walled cubic nanotube
- 2017
-
In: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 524, s. 137-143
-
Journal article (peer-reviewed)abstract
- The effect of surface shell parameters on the hysteresis loop behaviors of a decorated Ising cubic nanotube, consisting of a ferromagnetic spin-12 core which is interacting ferrimagnetically with a ferromagnetic spin-1 surface shell, is investigated, in the present work, within the effective-field theory with correlations based on the probability distribution technique. We have found that these parameters have a strong effect on the shape and the number of hysteresis loops and also on the coercive field and remanent magnetization behaviors. Indeed, triple, quintuple, septuple and nonuple hysteresis loop patterns have also been observed.
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| 46. |
- El Hamri, M., et al.
(author)
-
Investigation of the surface shell effects on the magnetic properties of a transverse antiferromagnetic Ising nanocube
- 2015
-
In: Superlattices and Microstructures. - : Elsevier BV. - 0749-6036 .- 1096-3677. ; 80, s. 151-168
-
Journal article (peer-reviewed)abstract
- The effective-field theory (EFT) with correlations based on the probability distribution technique has been used to study the magnetic properties of an antiferromagnetic cubic nanoparticle (nanocube). We have found that the surface shell parameters have strong effects on the compensation temperature, the magnetization profiles, coercivity, the shape and the number of the hysteresis loops for certain parameters. The effect of reduced temperature has also been examined on the hysteresis loops.
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| 47. |
- El Hamri, M., et al.
(author)
-
Magnetic behaviors of a transverse spin-1/2 Ising cubic nanowire with core/shell structure
- 2017
-
In: Physica. B, Condensed matter. - : Elsevier. - 0921-4526 .- 1873-2135. ; 507, s. 51-60
-
Journal article (peer-reviewed)abstract
- The surface shell exchange coupling effect on the magnetic properties (surface shell, core, total longitudinal and total transverse magnetizations, susceptibility, phase diagram and hysteresis loops) of a transverse spin-1/2 Ising cubic nanowire is investigated, in the present work, by employing the effective-field theory based on the probability distribution technique with correlations, for both ferro-and antiferromagnetic cases. We have found that this parameter has a strong effect on the magnetic properties in both cases. In the ferromagnetic case, the total longitudinal magnetization curves display Q-and S-type behaviors and the hysteresis loop has just one loop, whereas in the antiferromagnetic case, the N-type behavior, in which one compensation temperature appears below the critical temperature, exists in the total longitudinal magnetization curve versus reduced temperature, and triple hysteresis loops are found. The effect of applied field is also investigated on the total longitudinal magnetization for the both cases, and we have found that a large applied field value can overcome the antiferromagnetic coupling leading to a ferromagnetic-like behavior.
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| 48. |
- El Hamri, M., et al.
(author)
-
Magnetic properties of a diluted spin-1/2 Ising nanocube
- 2016
-
In: Physica A. - : Elsevier BV. - 0378-4371 .- 1873-2119. ; 443, s. 385-398
-
Journal article (peer-reviewed)abstract
- The effective-field theory with correlations based on the probability distribution technique is used to investigate the magnetic properties of a diluted Ising nanocube consisting of a ferromagnetic spin-1/2 core which is interacting antiferromagnetically with a ferromagnetic spin-1/2 surface shell. The effect of the concentration of magnetic atoms is examined. A number of interesting phenomena have been found such as the existence of the compensation temperature and triple hysteresis loops.
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| 49. |
- El Hamri, M., et al.
(author)
-
Magnetic Properties of a Diluted Transverse Spin-1 Ising Nanocube with a Longitudinal Crystal-Field
- 2017
-
In: INTERNATIONAL SYMPOSIUM ON CLUSTERS AND NANOMATERIALS. - : SPIE-INT SOC OPTICAL ENGINEERING. - 9781510608429
-
Conference paper (peer-reviewed)abstract
- In the present work, the effective field theory with correlations based on the probability distribution technique has been used to investigate the effect of the surface shell longitudinal cristal field on the magnetic properties of a diluted antiferromagnetic spin-1 Ising nanocube particle. This effect has also been studied on the hysteresis loops of the system. It is found that this parameter has a strong effect on the magnetization profiles, compensation temperature, coercive field and remanent magnetization.
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| 50. |
- El Hamri, M., et al.
(author)
-
Phase diagrams of a transverse cubic nanowire with diluted surface shell
- 2016
-
In: Applied Physics A. - : Springer Science and Business Media LLC. - 0947-8396 .- 1432-0630. ; 122:3
-
Journal article (peer-reviewed)abstract
- The effective-field theory with correlations based on the probability distribution technique has been used to investigate the phase diagrams (critical and compensation temperatures) of a transverse antiferromagnetic spin-1/2 Ising cubic nanowire with diluted surface shell. It is found that the phase diagrams of the system are strongly affected by the surface shell parameters. Indeed, two compensation points appear for certain values of Hamiltonian parameters, and the range of appearance of these latter points depends strongly on the surface shell transverse field.
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