Energy gaps, valence and conduction charge densities and optical properties of GaAs1−xPx

The electronic structure and its derived valence and conduction charge distributions along with the optical properties of zinc-blende GaAs[Formula: see text]P[Formula: see text] ternary alloys have been studied. The calculations are performed using a pseudopotential approach under the virtual crystal approximation (VCA) which takes into account the compositional disorder effect. Our findings are found to be generally in good accord with experiment. The composition dependence of direct and indirect bandgaps showed a clear bandgap bowing. The nature of the gap is found to depend on phosphorous content. The bonding and ionicity of the material of interest have been examined in terms of the anti-symmetric gap and charge densities. The variation in the optical constants versus phosphorous concentration has been discussed. The present investigation may give a useful applications in infrared and visible spectrum light emitters.

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Microhardness, phase transition, acoustic wave velocities and melting temperature of AlxGa1−xSb

International Journal of Modern Physics B ◽

10.1142/s0217979218502107 ◽

2018 ◽

Vol 32 (20) ◽

pp. 1850210 ◽

Cited By ~ 1

Author(s):

O. A. Al-Hagan ◽

H. Algarni ◽

N. Bouarissa ◽

M. Ajmal Khan ◽

T. F. Alhuwaymel

Keyword(s):

Acoustic Wave ◽

Melting Temperature ◽

Composition Dependence ◽

Ternary Alloys ◽

Virtual Crystal Approximation ◽

Al Content ◽

Wave Velocities ◽

Good Accord ◽

Compositional Disorder ◽

Pseudopotential Approach

The band structure of Al[Formula: see text]Ga[Formula: see text]Sb semiconducting ternary alloys and their related properties such as elastic constants, microhardness, transition pressure to the first phase, acoustic wave velocities and melting temperature have been investigated. The calculations are performed using a pseudopotential approach within the virtual crystal approximation which includes the effect of compositional disorder as an effective potential. Generally, our results are found to be in good accord with the experimental results. The composition dependence of all features of interest showed a monotonic behavior and suggests that the stiffness, hardness and structural stability becomes better in Al[Formula: see text]Ga[Formula: see text]Sb for higher Al concentrations. The bulk sound speeds and melting temperature are found to become larger when increasing the Al content.

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Calculation of Electronic and Optical Properties of Zinc-Blende MGX ZN1-X S

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.324.249 ◽

2011 ◽

Vol 324 ◽

pp. 249-252 ◽

Cited By ~ 1

Author(s):

Nadjla Mostefai ◽

Nadir Bouarissa ◽

Abdelhak Belkhir

Keyword(s):

Optical Properties ◽

Composition Dependence ◽

Ternary Alloys ◽

Virtual Crystal Approximation ◽

Electronic And Optical Properties ◽

Zinc Blende ◽

Blue Wavelength ◽

Indirect Band Gap ◽

Zinc Blende Structure ◽

Good Agreement

The electronic and optical properties of the MgxZn1-xS semiconductor ternary alloys crystallizing in the Zinc Blende structure are calculated using the empirical pseudopotential method (EPM) coupled with the virtual crystal approximation (VCA). The composition dependence of the direct and indirect band gap energies as well as the antisymmetric gap are investigated in the composition range 0 up to 1. Other quantities such as refractive index and coefficient of reflection are also obtained by means of different existing models. Our results are generally in good agreement with those available in the literature. The obtained informations could be useful for the feature design of blue wavelength optoelectronic devices.

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First-principles investigation of the structural, elastic, electronic, and optical properties of semiconducting AgBr1–xIx (0 ≤ x ≤ 1) ternary alloys in rock-salt and zinc blende structures

Canadian Journal of Physics ◽

10.1139/cjp-2019-0357 ◽

2020 ◽

Vol 98 (9) ◽

pp. 834-848

Author(s):

H. Rekab-Djabri ◽

Mohamed Drief ◽

Manal M. Abdus Salam ◽

Salah Daoud ◽

F. El Haj Hassan ◽

...

Keyword(s):

Optical Properties ◽

Band Gap ◽

Rock Salt ◽

Density Functional ◽

Local Density ◽

Ternary Alloys ◽

Full Potential ◽

Zinc Blende ◽

Lmto Method ◽

Direct Band

In this work, first principle calculations of the structural, electronic, elastic, and optical properties of novel AgBr1–xIx ternary alloys in rock-salt (B1) and zinc-blende (B3) structures are presented. The calculations were performed using the full-potential linear muffin-tin orbital (FP-LMTO) method within the framework of the density functional theory (DFT). The exchange and correlation potentials were treated according to the local density approximation (LDA). The lattice constants for the B1 and B3 phases versus iodide concentration (x) were found to deviate slightly from the linear relationship of Vegard’s law. The calculated electronic properties showed that AgBr1–xIx alloys in the B3 structure have a direct band gap (Γ – Γ) for all concentrations of x, which means that they can be used in long-wavelength optoelectronic applications, while in the B1 structure they have an indirect (Γ – R) band gap. The elastic constants Cij, shear modulus G, Young’s modulus E, Poisson’s ratio ν, index of ductility B/G, sound velocities vt, vl, and vm, and Debye temperature θD were also reported and analyzed. By incorporating the basic optical properties, we discussed the dielectric function, refractive index, optical reflectivity, absorption coefficient, and optical conductivity in terms of incident photon energy up to 13.5 eV. The present results were found to be in good agreement with the available experimental and other theoretical results.

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First-principles study of optical properties in Ca-doped ZnO alloys

Open Physics ◽

10.2478/s11534-012-0099-7 ◽

2012 ◽

Vol 10 (5) ◽

Author(s):

Li-Na Bai ◽

Jian-She Lian ◽

Wei-Tao Zheng ◽

Qing Jiang

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Optical Transition ◽

High Energy ◽

Ternary Alloys ◽

Potential Candidate ◽

Coulomb Interactions ◽

Generalized Gradient ◽

Light Emitters

AbstractVarious electronic and optical properties of Zn1−x CaxO ternary alloys of wurtzite structure are calculated using a first-principles approach based on the framework of the generalized gradient approximation to density-functional theory. In particular, on-site Coulomb interactions are introduced, which can reasonably well predict the electronic properties and band gaps of the Zn1−x CaxO (0≤x≤0.25) system. The imaginary part of the calculated dielectric function indicates that the optical transition between O 2p states in the valence band and Zn 4s states in the conduction band shifts to the high-energy range as the Ca concentration increases. The calculated band gap shows a significant increase with increasing Ca concentration. Therefore, Zn1−x CaxO ternary alloys may be a potential candidate alloy for optoelectronic materials, and especially for light-emitters and detectors.

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Electronic and optical properties of ternary alloys ZnxCd1−xS, ZnxCd1−xSe, ZnSxSe1−x, MgxZn1−xSe

Materials Science-Poland ◽

10.1515/msp-2017-0005 ◽

2017 ◽

Vol 35 (1) ◽

pp. 32-39

Author(s):

K. Benchikh ◽

H. Abid ◽

M. Benchehima

Keyword(s):

Optical Properties ◽

Detailed Comparison ◽

Ternary Alloys ◽

Band Structures ◽

Virtual Crystal Approximation ◽

Electronic And Optical Properties ◽

Empirical Pseudopotential Method ◽

Direct Band ◽

Alloy Concentration ◽

Good Agreement

AbstractThe empirical pseudopotential method (EPM) within the virtual crystal approximation (VCA) is used to calculate the electronic and optical properties of ternary alloys ZnxCd1−xS, ZnxCd1−xSe, ZnSxSe1−x and MgxZn1−xSe. The alloy band structures and energy gaps are calculated using VCA which incorporates the compositional disorder as an effective potential. The calculated band structures for the ZnxCd1−xS, ZnxCd1−xSe and ZnSxSe1−x alloys show a direct band gap in the whole range of the concentration except for the MgxZn1−xSe alloy which presents a crossover from the direct gap to the indirect one.Also the dependence of the refractive index on the concentration is calculated for each ternary alloy. This parameter is found to depend nonlinearly on the alloy concentration. A detailed comparison of our results with experimental data and works of other authors has led to a good agreement.

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First principle characterization of structural, electronic, mechanical, thermodynamic, linear and nonlinear optical properties of zinc blende InAs, InSb and their InAsxSb1-x ternary alloys

Journal of Physics and Chemistry of Solids ◽

10.1016/j.jpcs.2019.04.031 ◽

2019 ◽

Vol 132 ◽

pp. 213-221 ◽

Cited By ~ 2

Author(s):

Y. Asadi ◽

Z. Nourbakhsh

Keyword(s):

Optical Properties ◽

Nonlinear Optical ◽

Nonlinear Optical Properties ◽

Ternary Alloys ◽

First Principle ◽

Zinc Blende ◽

Linear And Nonlinear

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Exciton-related optical properties in zinc-blende GaN/InGaN quantum wells under hydrostatic pressure

physica status solidi (b) ◽

10.1002/pssb.201451402 ◽

2015 ◽

Vol 252 (4) ◽

pp. 670-677 ◽

Cited By ~ 10

Author(s):

C. M. Duque ◽

A. L. Morales ◽

M. E. Mora-Ramos ◽

C. A. Duque

Keyword(s):

Optical Properties ◽

Hydrostatic Pressure ◽

Quantum Wells ◽

Zinc Blende ◽

Ingan Quantum Wells

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Rhodanine-based dyes absorbing in the entire visible spectrum

Organic Chemistry Frontiers ◽

10.1039/c6qo00760k ◽

2017 ◽

Vol 4 (6) ◽

pp. 1024-1028 ◽

Cited By ~ 3

Author(s):

Rafael Sandoval-Torrientes ◽

Joaquín Calbo ◽

David García-Fresnadillo ◽

José Santos ◽

Enrique Ortí ◽

...

Keyword(s):

Optical Properties ◽

Dft Calculations ◽

Electrochemical Characterizations ◽

Visible Spectrum ◽

Electronic And Optical Properties ◽

Entire Visible Spectrum

A series of new broad-absorbing rhodanine-fluorene dyes conjugated with triarylamines are presented. Spectroscopic and electrochemical characterizations, along with theoretical DFT calculations, unveil the electronic and optical properties of the dyes.

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