S. Hossein Ganjipour; Ebrahim Sadeghi
Abstract
The present study seeks to scrutinize a two bosonic atoms system in the presence of a two-dimensional anharmonic and a short range interatomic potentials. The wave functions and energies of the harmonic part are analytically stated, and the effect of anharmonic term on the energy for different strengths ...
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The present study seeks to scrutinize a two bosonic atoms system in the presence of a two-dimensional anharmonic and a short range interatomic potentials. The wave functions and energies of the harmonic part are analytically stated, and the effect of anharmonic term on the energy for different strengths of interaction is calculated. The results show that the relative motion and correction energy have different behaviors with the interaction strength. To investigate the dynamics of system, the fidelity for different coupling strengths is also calculated. The results are in good agreement with other works
noushin dadashzadeh; Elnaz Pourreza
Abstract
In this comparative study, our objective is to design a dielectric barrier discharge (DBD) reactor under atmospheric pressure. The current need is to characterize the plasma properties and optimize the designed plasma system under variable conditions. In this paper, a one-dimensional time-dependent simulation ...
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In this comparative study, our objective is to design a dielectric barrier discharge (DBD) reactor under atmospheric pressure. The current need is to characterize the plasma properties and optimize the designed plasma system under variable conditions. In this paper, a one-dimensional time-dependent simulation of a DBD device, driven by a sinusoidal RF voltage with an amplitude of 755 kV at 52 kHz, in argon gas is shown. The DBD device, with two electrodes, covered by dielectric material and with variable dielectric constant between 2, 5 and 8 was considered, and the discharge parameters were simulated in terms of time across the plasma space to find an optimal dielectric constant for delivering maximum power deposition. Using a sinusoidal voltage to DBD device with different dielectric constant, electric field profiles, electron density, electron temperature, mass fraction of argon atoms, average electron energy, ion current density, electron current density, plasma, and power deposition are shown.
maryam azizi; hamdollah salehi
Abstract
In this study, the structural and optical properties such as refractive index, extinction coefficient, absorption coefficient, reflection coefficient, and optical conductivity of the monoclinic crystalline structure compound Ag2SiS3 are investigated using theoretical calculations. The LDA approximation ...
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In this study, the structural and optical properties such as refractive index, extinction coefficient, absorption coefficient, reflection coefficient, and optical conductivity of the monoclinic crystalline structure compound Ag2SiS3 are investigated using theoretical calculations. The LDA approximation with the pseudo-potential method, and from the density of states diagram, the value of the band gap are 1.2 eV, 1.4 eV, and 2.37 eV, in the LDA and LDA+U and HSE approximations, respectively, were obtained with norm conserving pseudo-potential. Also, the calculated bulk modulus value were 81 GPa in LDA, 79.4 GPa in LDA+U, and 76.5 GPa in HSE approximation. Finally, the optical properties such as refractive index, extinction coefficient, absorption coefficient, reflection coefficient and optical conductivity were examined. From the examination of the optical properties, the optical gap value obtained from the absorption coefficient is in good agreement with the band gap value, which is Optical coefficients are different in different directions due to the anisotropy of the structure. The value of the optical gap that read from the absorption coefficient diagram in the approximation of LDA, LDA+U and HSE were 1.27 eV, 1.4 eV and 2.37 eV, respectively. Based on the optical investigations, this compound is useful in solar cells and optoelectronic materials.
Maryam Esrafilian; Nadia Salami; Aliasghar shokri
Abstract
In this study, the thermoelectric properties of system based on molybdenum disulfide and tungsten di-telluride are investigated in three combinations with two identical nanoribbons of molybdenum disulfide and tungsten di-telluride in the upper and lower layer, as well as a structure with two different ...
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In this study, the thermoelectric properties of system based on molybdenum disulfide and tungsten di-telluride are investigated in three combinations with two identical nanoribbons of molybdenum disulfide and tungsten di-telluride in the upper and lower layer, as well as a structure with two different layer, one molybdenum disulfide and the other tungsten-di-telluride. These properties include the electrical conductivity coefficient (G), thermal conductivity (κe), Seebeck coefficient or thermoelectric power (S) and efficiency coefficient (ZTe). which are suitable for the design of thermoelectric devices. The effect of the type of combinations of two-dimensional heterogeneous structures and temperature on thermodynamic properties was investigated. The results show that molybdenum-disulfide/tungsten-di-telluride configuration with Armchair edge structure has the most desirable thermoelectric properties. The results of this article can be useful in the design of nano electric devices based on two-dimensional layers.
Azadeh Ahmadian
Abstract
In this research, we investigate and compare the optical properties of lead borate and bismuth borate glasses. We used the Refractive index and the energy band gaps determined experimentally in Ref [22]. We found that molar refraction and electronic polarizability demonstrate similar behavior. The metallization ...
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In this research, we investigate and compare the optical properties of lead borate and bismuth borate glasses. We used the Refractive index and the energy band gaps determined experimentally in Ref [22]. We found that molar refraction and electronic polarizability demonstrate similar behavior. The metallization varies from 0.630 to 0.568 for lead borate glasses and from 0.526 to 0.435 for bismuth borate glasses with increasing PbO/Bi2O3 content. The transmission coefficient decreased from 0.884 to 0.846 for PbB glasses and from 0.818 to 0.751 for BiB glasses, while the dielectric constant increased from 2.755 to 3.276 for PbB glasses and from 3.094 to 4.884 for BiB glasses. The optical electronegativity decreased from 0.964 to 0.792 for PbB and from 0.857 to 0.760 for BiB. The linear dielectric susceptibility increased from 0.139 to 0.181 for lead borate glasses and from 0.214 to 0.309 for bismuth borate glasses. The nonlinear optical susceptibility changed from 0.647 to 1.829 esu for PbB and from 0.359 to 1.551 esu for BiB , indicating more than fivefold increment. The nonlinear refraction index varied from 1.470 to 3.810 esu for lead borate glasses and from 0.704 to 2.646 esu for bismuth borate glasses. The results confirm that bismuth borate is better than lead borate for optical applications
Neda Ahmadi
Abstract
In this work, a lead-free double perovskite solar cell has been investigated and the effect of a periodic array of spherical Au nanoparticles coated with Silica (Au@SiO2) and Titania (Au@TiO2) nanorod has been studied and compared to the effect of bare Au nanoparticles. We propose a p-i-n perovskite ...
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In this work, a lead-free double perovskite solar cell has been investigated and the effect of a periodic array of spherical Au nanoparticles coated with Silica (Au@SiO2) and Titania (Au@TiO2) nanorod has been studied and compared to the effect of bare Au nanoparticles. We propose a p-i-n perovskite solar cell with architecture ITO/PEDOT:PSS/ Cs2AgBiBr6/ Tio2/ Ag. In this study, three-dimensional Finite-difference Time-domain method utilizing FDTD module of Ansys-Lumerical software has been used and the wavelength range is from ultraviolet, 300nm to near-infrared (NIR), 1100 nm. The effect of these nanoparticles on light absorption, electric field intensity, short-circuit current density, generation rate, and current from the simulation device has been investigated. The results show that the effect of Au@TiO2 on the efficiency enhancement of solar cells is higher than other nanoparticles. In addition, the current from the simulation device increases by 17.8%, short-circuit current density is enhanced by 17.85%, and the maximum generation rate grows 100 times. This result is due to the plasmonic near-field of nanoparticles and light scattering from them. Moreover, the place of Au@SiO2 periodic array has been changed and the effect of nanoparticles’ location inside the perovskite layer has been investigated.