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Papers by Ahmed Rebey

Research paper thumbnail of Thermal processes contributions to the temperature dependence of the energy gap in dilute bismuth III-V alloys

Solid State Communications, 2022

Research paper thumbnail of MOVPE growth of InAsBi/InAs/GaAs heterostructure analyzed by in situ spectral reflectance

Journal of Materials Science: Materials in Electronics, 2017

InAsBi/InAs heterostructure was grown on semi-insulating GaAs substrate by atmospheric pressure M... more InAsBi/InAs heterostructure was grown on semi-insulating GaAs substrate by atmospheric pressure MOVPEat a temperature of 375 °C. Trimethylbismuth (TMBi), Abstract InAsBi/InAs heterostructures were elaborated on semi-insulating GaAs substrate by atmospheric pressure metalorganic vapor phase epitaxy. Spectral reflectance in the range of 400-800 nm was employed to in situ monitor epitaxy. In order to determine optical constants of InAsBi films, an optical model incorporating two parameters: timedependent surface roughness and time-dependent growth rate was established to simulate the in situ reflectance. Since bismuth has a crucial effect on surface kinetic mechanisms during growth of III-V semiconductors, a theoretical motivation introducing these two parameters instead of a standard single rms roughness and growth rate was provided. In order to evaluate the structural and optical properties of this material, reflectivity responses were analyzed for several wavelengths. Results were ex situ correlated with atomic force microscopy measurements.

Research paper thumbnail of Calculation of InAsBi ternary phase diagram

Vacuum, 2016

The phase diagrams of the IneAseBi system were predicted at different temperatures by using the C... more The phase diagrams of the IneAseBi system were predicted at different temperatures by using the Calphad method. The calculations were based on the thermodynamic properties of the constituent binary systems. These properties were collected from selected literature. They were then used to calculate the constituent binary phase diagrams (IneAs, IneBi and AseBi) and the results were compared with the experimentally determined phase diagrams for evaluating the reliability of the binary data before the ternary phase diagrams were calculated. The isothermal sections at different temperatures and liquidus projection of the IneAseBi ternary system were calculated. The calculated results predict the domination of solid phases at low temperatures and show also that the fusion temperature depends on crystallographic structure of InAsBi and the chemical Bi and In concentrations. Such results were helpful for successful growth of InAsBi alloys.

Research paper thumbnail of Bismuth catalyzed growth of GaAsBi nanowires by metalorganic vapor phase epitaxy

Materials Letters, 2015

We report the synthesis of GaAsBi nanowires using Bi as catalyst. Nanoislands of bismuth are grow... more We report the synthesis of GaAsBi nanowires using Bi as catalyst. Nanoislands of bismuth are grown on GaAs substrates by atmospheric pressure metalorganic vapor phase epitaxy, these acts appear as local points of the nucleus for the growth of the GaAsBi nanowires. Catalysis by the metal droplet can make growth possible at low temperatures. Surface morphology of the elaborated samples is investigated using scanning electron microscopy. The growth of the nanowires at low temperature results in round Bi-rich balls can be found on the tips of all nanostructures. The growth conditions affect the initial nucleation of GaAsBi structures, resulting in different numbers and shapes of nanowires. The bases of the tapered structures can be quite large. Likewise, the growth conditions have also a great impact on the orientation and structural quality of the nanowires.

Research paper thumbnail of AP-MOVPE of InGaAs on GaAs (001): Analysis of in situ reflectivity response

Microelectronics Journal, 2008

We have investigated in situ monitoring of growth rate and refractive index by laser reflectometr... more We have investigated in situ monitoring of growth rate and refractive index by laser reflectometry during InGaAs on GaAs (001) substrate growth in atmospheric pressure metalorganic vapour-phase epitaxy (AP-MOVPE). The indium solid composition (xIns) was varied by changing the substrate temperature or the indium vapour composition (xInv). The refractive index of InGaAs alloys as a function of temperature and composition

Research paper thumbnail of In situ monitoring of InAsBi alloy grown under alternated bismuth flows by metalorganic vapor phase epitaxy

Materials Science and Engineering: B, 2019

Abstract We suggest a successful growth method for InAsBi layer epitaxy on (0 0 1) GaAs substrate... more Abstract We suggest a successful growth method for InAsBi layer epitaxy on (0 0 1) GaAs substrate. An alternated trimethylbismuth flows was used during growth. For real time monitoring of the metalorganic vapor-phase epitaxy of InAsBi layer, we use spectral reflectance. Reflectivity signal is found to change significantly during both InAsBi and InAs growth stages. High-resolution X-ray diffraction (HRXRD) curve shows a wide peak that can be attributed to InAsBi inhomogeneous layer. Based on the signals of several wavelengths in situ monitoring system, the related information of growth rate, refractive index n and the extinction coefficient k of InAs and InAsBi sequences were determined. Simulation results indicate different Bi regions. Theoretical simulation of reflectivity signals was carried out by recurrence method using a multilayer model. Results were ex-situ correlated with atomic force microscopy measurements.

Research paper thumbnail of Strain study of GaAs/In x Ga 1−x As/GaAs structures grown by MOVPE

Surface and Coatings Technology, 2016

Abstract GaAs/InxGa1 − xAs/GaAs strained and partially relaxed structures were grown by metalorga... more Abstract GaAs/InxGa1 − xAs/GaAs strained and partially relaxed structures were grown by metalorganic vapor phase epitaxy and in situ monitored by laser reflectometry (LR). Two structures were formed by a single InxGa1 − xAs layer, and the third comprises three superposed InxGa1 − xAs layers having increasing indium contents. LR plots as function of time were recorded to extract growth rates and thicknesses of active and cap layers. In order to study the strain effect on structural and optical properties of these heterostructures, high resolution X-ray diffraction (HRXRD) and photoreflectance (PR) measurements were performed. HRXRD curves are developed to calculate strain tensor components, indium composition, and thicknesses of strained and partially relaxed layers. Besides, valence-band splitting and band-gap energy shift were measured by best fitting PR spectra at 300 K. Experimental energy values determined as a function of indium composition and relaxation rate were compared to those obtained by the elastic strain theory. For single and superposed InxGa1 − xAs active layers, a good correlation between experimental results and theoretical predictions was obtained.

Research paper thumbnail of Thermodynamic study of the ternary system gallium-arsenic-bismuth

physica status solidi (c), 2014

Research paper thumbnail of Surface analysis of different oriented GaAs substrates annealed under bismuth flow

Journal of Crystal Growth, 2007

Research paper thumbnail of Spectroscopic ellipsometry study of GaAs1−xBix material grown on GaAs substrate by atmospheric pressure metal-organic vapor-phase epitaxy

Applied Physics Letters, 2009

The optical properties in terms of complex dielectric function of GaAs1-xBix alloys (0%&a... more The optical properties in terms of complex dielectric function of GaAs1-xBix alloys (0%<=x<=3.7%), grown by atmospheric pressure metal-organic vapor-phase epitaxy, are determined by using room temperature spectroscopic ellipsometry. The interband transition energies in the energy range of 1.4-5.4 eV are resolved using a line shape fitting on the numerically calculated dielectric function second derivatives. The bismuth effect on the critical

Research paper thumbnail of Oxidation of bismuth nanodroplets deposit on GaAs substrate

Research paper thumbnail of Optical monitoring of the growth rate reduction by CCl4 during metalorganic vapour-phase epitaxy deposition of carbon doped GaAs

Journal of Crystal Growth, 1998

Metalorganic vapor-phase epitaxy (MOVPE) growth of heavily doped GaAs has been studied by reflect... more Metalorganic vapor-phase epitaxy (MOVPE) growth of heavily doped GaAs has been studied by reflectometry with a 632.8nm laser beam. The measurement of reflection intensity gives the growth rate and the morphology of the layer. Small changes in the refractive index due to high carbon doping (1020cm−3 and above) gives rise to oscillations in the reflectometric signal. A reduction in the growth rate of C-doped GaAs, was attributed to the etching by GaClx (x=1–3) species associated with the use of CCl4. There is no significant change in the growth rate if the growth temperature is smaller than a critical value depending on [Ga(CH3)3]/[CCl4] ratio. However, above this critical temperature, a steep decrease in the growth rate and a poor morphology of the surface layer are observed and lead to the reduction in reflection intensities. These results are analyzed using microscopic observations and a thermodynamic calculation.

Research paper thumbnail of Study of Surface Stability and Electronic Structure of a Bi-terminated InAs (001) Surface Based on Ab Initio Calculations

Journal of Electronic Materials, 2021

In the present work, we have performed a detailed study on the influence of Bi adsorption on the ... more In the present work, we have performed a detailed study on the influence of Bi adsorption on the structural and electronic properties of the InAs (001) surface. We have considered five prototypes of Bi/InAs (001)-β2(2 × 4) and α2(2 × 4) structures with different Bi coverage Θ. We have revealed that the substitution of As dimers by Bi atoms introduces structural and geometrical change on the InAs (001) surface. At As-rich conditions, our obtained results prove that the increasing of Bi coverage Θ can stabilize the Bi/InAs (001) structure. The electronic structure of the β2 and α2 are also presented.

Research paper thumbnail of Stark effect in GaNAsBi/GaAs quantum wells operating at 1.55μm

Thin Solid Films, 2014

ABSTRACT The effect of an applied stationary electric field on the band structure of GaNAsBi/GaAs... more ABSTRACT The effect of an applied stationary electric field on the band structure of GaNAsBi/GaAs quantum wells has been investigated using self-consistent calculation. Such study based on the optimization of N and Bi contents can be useful to improve physical properties of emitters or photodetector devices operating at 1.55 μm. We have examined the quantum confined Stark effect on the shape of the confining potential, the Fermi level, the subband energies and their corresponding wavefunctions. We have also determined the oscillator strength and the absorption coefficient of the inter-band transitions and their dependences on the applied perturbation.

Research paper thumbnail of Analysis of Growth Mechanisms and Microstructure Evolution of Pb+2 Minor Concentrations by Electrodeposition Technique

In this study, the electrodeposition technique has been used to deposit low concentrations of hig... more In this study, the electrodeposition technique has been used to deposit low concentrations of highly toxic lead (Pb) cations into a solution of nitrate at a constant potential of -1V on fluorine-doped tin oxide electrodes (FTO). Monitoring of the reaction was conducted with the assistance of a computerized potentiostat/galvanostat setup, in cyclic voltammetry and in situ chronoamperometry modes. X-ray diffraction, scanning electron microscopy, energy dispersive X-Ray, and ultraviolet-visible spectroscopy techniques were used to examine the crystal structure, morphology, and optical properties of the lead deposits, respectively. Pb regular micro-hexagons have been identified; their size and density were significantly influenced by the cationic precursor’s concentration. The correlation between the morphological and crystallographical structures of the electrodeposits was discussed. Based on chronoamperometric measurements, a mechanism for the growth of Pb deposits on FTO substrate ha...

Research paper thumbnail of Spontaneous Emission Rate and Radiative Current Density in p-GaAs/i-GaNAsBi/n-GaAs Quantum Well Lasers

Journal of Computational and Theoretical Nanoscience

We have theoretically investigated the 1.55 μm emission of p–i–n GaNAsBi-based quantum wells (QWs... more We have theoretically investigated the 1.55 μm emission of p–i–n GaNAsBi-based quantum wells (QWs) using a self-consistent calculation combined with (16×16) BAC model. Their performances are evaluated in terms of spontaneous emission rate Rsp and radiative current density Jrad. We have found that Jrad increases as function of the injected carrier density as well as the doping density. The quantum confined Stark effect on radiative current density in ideal lasers is also discussed. The radiative current density versus well width for simple and double p-GaAs/i-GaN·58yAs1-1·58yBiy/n-GaAs quantum well structures is also examined. We have obtained that Jrad increases with increase average thickness of GaNAsBi active region. The optimization of well parameters can be used as a basis for GaNAsBi-based lasers intended for optical fiber telecommunication wavelength.

Research paper thumbnail of Adsorption of Bi adatom on InAs (001) – β2 (2 × 4) and α2 (2 × 4) surface: A first principles study

Materials Science in Semiconductor Processing

Research paper thumbnail of First-principles study of atomic and electronic structure of Bi/ InP (001)-α2 (2x4) and β2 (2x4) surfaces

Materials Research Express

Research paper thumbnail of Effect of V/III ratio on the optical properties of (3 1 1)A and (3 1 1) B oriented InAlAs/InP heterostructures

Research paper thumbnail of Theoretical study of the carrier effective mass in diluted III-N-V semiconductor alloys by using 10-band k.p model

Thin Solid Films

The dependence of carrier effective mass of GaN x As 1 − x , InN x P 1 − x , InN x As 1 − x , and... more The dependence of carrier effective mass of GaN x As 1 − x , InN x P 1 − x , InN x As 1 − x , and InN x Sb 1 − x alloys on nitrogen content is investigated using a 10-band k.p model. The electron effective mass m e ⁎ at the bottom of conduction band in GaN x As 1 − x and InN x P 1 − x exhibits a gradual increase as a function of N concentration in the range 0− 1% and a decrease of x value between 1 and 5%. However, the behavior of m e ⁎ in InN x As 1 − x and InN x Sb 1 − x shows a strong decrease in all studied x-range. Our results are compared to the available data reported in the literature. On the other hand, contrary to heavy-hole effective mass m hh ⁎ , the light-hole effective mass m lh ⁎ in all studied alloys is significantly affected by nitrogen states, which modify the non-parabolicity of the LH band. The modification of the carrier effective mass affects the transport properties of the III-N-V alloys.

Research paper thumbnail of Thermal processes contributions to the temperature dependence of the energy gap in dilute bismuth III-V alloys

Solid State Communications, 2022

Research paper thumbnail of MOVPE growth of InAsBi/InAs/GaAs heterostructure analyzed by in situ spectral reflectance

Journal of Materials Science: Materials in Electronics, 2017

InAsBi/InAs heterostructure was grown on semi-insulating GaAs substrate by atmospheric pressure M... more InAsBi/InAs heterostructure was grown on semi-insulating GaAs substrate by atmospheric pressure MOVPEat a temperature of 375 °C. Trimethylbismuth (TMBi), Abstract InAsBi/InAs heterostructures were elaborated on semi-insulating GaAs substrate by atmospheric pressure metalorganic vapor phase epitaxy. Spectral reflectance in the range of 400-800 nm was employed to in situ monitor epitaxy. In order to determine optical constants of InAsBi films, an optical model incorporating two parameters: timedependent surface roughness and time-dependent growth rate was established to simulate the in situ reflectance. Since bismuth has a crucial effect on surface kinetic mechanisms during growth of III-V semiconductors, a theoretical motivation introducing these two parameters instead of a standard single rms roughness and growth rate was provided. In order to evaluate the structural and optical properties of this material, reflectivity responses were analyzed for several wavelengths. Results were ex situ correlated with atomic force microscopy measurements.

Research paper thumbnail of Calculation of InAsBi ternary phase diagram

Vacuum, 2016

The phase diagrams of the IneAseBi system were predicted at different temperatures by using the C... more The phase diagrams of the IneAseBi system were predicted at different temperatures by using the Calphad method. The calculations were based on the thermodynamic properties of the constituent binary systems. These properties were collected from selected literature. They were then used to calculate the constituent binary phase diagrams (IneAs, IneBi and AseBi) and the results were compared with the experimentally determined phase diagrams for evaluating the reliability of the binary data before the ternary phase diagrams were calculated. The isothermal sections at different temperatures and liquidus projection of the IneAseBi ternary system were calculated. The calculated results predict the domination of solid phases at low temperatures and show also that the fusion temperature depends on crystallographic structure of InAsBi and the chemical Bi and In concentrations. Such results were helpful for successful growth of InAsBi alloys.

Research paper thumbnail of Bismuth catalyzed growth of GaAsBi nanowires by metalorganic vapor phase epitaxy

Materials Letters, 2015

We report the synthesis of GaAsBi nanowires using Bi as catalyst. Nanoislands of bismuth are grow... more We report the synthesis of GaAsBi nanowires using Bi as catalyst. Nanoislands of bismuth are grown on GaAs substrates by atmospheric pressure metalorganic vapor phase epitaxy, these acts appear as local points of the nucleus for the growth of the GaAsBi nanowires. Catalysis by the metal droplet can make growth possible at low temperatures. Surface morphology of the elaborated samples is investigated using scanning electron microscopy. The growth of the nanowires at low temperature results in round Bi-rich balls can be found on the tips of all nanostructures. The growth conditions affect the initial nucleation of GaAsBi structures, resulting in different numbers and shapes of nanowires. The bases of the tapered structures can be quite large. Likewise, the growth conditions have also a great impact on the orientation and structural quality of the nanowires.

Research paper thumbnail of AP-MOVPE of InGaAs on GaAs (001): Analysis of in situ reflectivity response

Microelectronics Journal, 2008

We have investigated in situ monitoring of growth rate and refractive index by laser reflectometr... more We have investigated in situ monitoring of growth rate and refractive index by laser reflectometry during InGaAs on GaAs (001) substrate growth in atmospheric pressure metalorganic vapour-phase epitaxy (AP-MOVPE). The indium solid composition (xIns) was varied by changing the substrate temperature or the indium vapour composition (xInv). The refractive index of InGaAs alloys as a function of temperature and composition

Research paper thumbnail of In situ monitoring of InAsBi alloy grown under alternated bismuth flows by metalorganic vapor phase epitaxy

Materials Science and Engineering: B, 2019

Abstract We suggest a successful growth method for InAsBi layer epitaxy on (0 0 1) GaAs substrate... more Abstract We suggest a successful growth method for InAsBi layer epitaxy on (0 0 1) GaAs substrate. An alternated trimethylbismuth flows was used during growth. For real time monitoring of the metalorganic vapor-phase epitaxy of InAsBi layer, we use spectral reflectance. Reflectivity signal is found to change significantly during both InAsBi and InAs growth stages. High-resolution X-ray diffraction (HRXRD) curve shows a wide peak that can be attributed to InAsBi inhomogeneous layer. Based on the signals of several wavelengths in situ monitoring system, the related information of growth rate, refractive index n and the extinction coefficient k of InAs and InAsBi sequences were determined. Simulation results indicate different Bi regions. Theoretical simulation of reflectivity signals was carried out by recurrence method using a multilayer model. Results were ex-situ correlated with atomic force microscopy measurements.

Research paper thumbnail of Strain study of GaAs/In x Ga 1−x As/GaAs structures grown by MOVPE

Surface and Coatings Technology, 2016

Abstract GaAs/InxGa1 − xAs/GaAs strained and partially relaxed structures were grown by metalorga... more Abstract GaAs/InxGa1 − xAs/GaAs strained and partially relaxed structures were grown by metalorganic vapor phase epitaxy and in situ monitored by laser reflectometry (LR). Two structures were formed by a single InxGa1 − xAs layer, and the third comprises three superposed InxGa1 − xAs layers having increasing indium contents. LR plots as function of time were recorded to extract growth rates and thicknesses of active and cap layers. In order to study the strain effect on structural and optical properties of these heterostructures, high resolution X-ray diffraction (HRXRD) and photoreflectance (PR) measurements were performed. HRXRD curves are developed to calculate strain tensor components, indium composition, and thicknesses of strained and partially relaxed layers. Besides, valence-band splitting and band-gap energy shift were measured by best fitting PR spectra at 300 K. Experimental energy values determined as a function of indium composition and relaxation rate were compared to those obtained by the elastic strain theory. For single and superposed InxGa1 − xAs active layers, a good correlation between experimental results and theoretical predictions was obtained.

Research paper thumbnail of Thermodynamic study of the ternary system gallium-arsenic-bismuth

physica status solidi (c), 2014

Research paper thumbnail of Surface analysis of different oriented GaAs substrates annealed under bismuth flow

Journal of Crystal Growth, 2007

Research paper thumbnail of Spectroscopic ellipsometry study of GaAs1−xBix material grown on GaAs substrate by atmospheric pressure metal-organic vapor-phase epitaxy

Applied Physics Letters, 2009

The optical properties in terms of complex dielectric function of GaAs1-xBix alloys (0%&a... more The optical properties in terms of complex dielectric function of GaAs1-xBix alloys (0%<=x<=3.7%), grown by atmospheric pressure metal-organic vapor-phase epitaxy, are determined by using room temperature spectroscopic ellipsometry. The interband transition energies in the energy range of 1.4-5.4 eV are resolved using a line shape fitting on the numerically calculated dielectric function second derivatives. The bismuth effect on the critical

Research paper thumbnail of Oxidation of bismuth nanodroplets deposit on GaAs substrate

Research paper thumbnail of Optical monitoring of the growth rate reduction by CCl4 during metalorganic vapour-phase epitaxy deposition of carbon doped GaAs

Journal of Crystal Growth, 1998

Metalorganic vapor-phase epitaxy (MOVPE) growth of heavily doped GaAs has been studied by reflect... more Metalorganic vapor-phase epitaxy (MOVPE) growth of heavily doped GaAs has been studied by reflectometry with a 632.8nm laser beam. The measurement of reflection intensity gives the growth rate and the morphology of the layer. Small changes in the refractive index due to high carbon doping (1020cm−3 and above) gives rise to oscillations in the reflectometric signal. A reduction in the growth rate of C-doped GaAs, was attributed to the etching by GaClx (x=1–3) species associated with the use of CCl4. There is no significant change in the growth rate if the growth temperature is smaller than a critical value depending on [Ga(CH3)3]/[CCl4] ratio. However, above this critical temperature, a steep decrease in the growth rate and a poor morphology of the surface layer are observed and lead to the reduction in reflection intensities. These results are analyzed using microscopic observations and a thermodynamic calculation.

Research paper thumbnail of Study of Surface Stability and Electronic Structure of a Bi-terminated InAs (001) Surface Based on Ab Initio Calculations

Journal of Electronic Materials, 2021

In the present work, we have performed a detailed study on the influence of Bi adsorption on the ... more In the present work, we have performed a detailed study on the influence of Bi adsorption on the structural and electronic properties of the InAs (001) surface. We have considered five prototypes of Bi/InAs (001)-β2(2 × 4) and α2(2 × 4) structures with different Bi coverage Θ. We have revealed that the substitution of As dimers by Bi atoms introduces structural and geometrical change on the InAs (001) surface. At As-rich conditions, our obtained results prove that the increasing of Bi coverage Θ can stabilize the Bi/InAs (001) structure. The electronic structure of the β2 and α2 are also presented.

Research paper thumbnail of Stark effect in GaNAsBi/GaAs quantum wells operating at 1.55μm

Thin Solid Films, 2014

ABSTRACT The effect of an applied stationary electric field on the band structure of GaNAsBi/GaAs... more ABSTRACT The effect of an applied stationary electric field on the band structure of GaNAsBi/GaAs quantum wells has been investigated using self-consistent calculation. Such study based on the optimization of N and Bi contents can be useful to improve physical properties of emitters or photodetector devices operating at 1.55 μm. We have examined the quantum confined Stark effect on the shape of the confining potential, the Fermi level, the subband energies and their corresponding wavefunctions. We have also determined the oscillator strength and the absorption coefficient of the inter-band transitions and their dependences on the applied perturbation.

Research paper thumbnail of Analysis of Growth Mechanisms and Microstructure Evolution of Pb+2 Minor Concentrations by Electrodeposition Technique

In this study, the electrodeposition technique has been used to deposit low concentrations of hig... more In this study, the electrodeposition technique has been used to deposit low concentrations of highly toxic lead (Pb) cations into a solution of nitrate at a constant potential of -1V on fluorine-doped tin oxide electrodes (FTO). Monitoring of the reaction was conducted with the assistance of a computerized potentiostat/galvanostat setup, in cyclic voltammetry and in situ chronoamperometry modes. X-ray diffraction, scanning electron microscopy, energy dispersive X-Ray, and ultraviolet-visible spectroscopy techniques were used to examine the crystal structure, morphology, and optical properties of the lead deposits, respectively. Pb regular micro-hexagons have been identified; their size and density were significantly influenced by the cationic precursor’s concentration. The correlation between the morphological and crystallographical structures of the electrodeposits was discussed. Based on chronoamperometric measurements, a mechanism for the growth of Pb deposits on FTO substrate ha...

Research paper thumbnail of Spontaneous Emission Rate and Radiative Current Density in p-GaAs/i-GaNAsBi/n-GaAs Quantum Well Lasers

Journal of Computational and Theoretical Nanoscience

We have theoretically investigated the 1.55 μm emission of p–i–n GaNAsBi-based quantum wells (QWs... more We have theoretically investigated the 1.55 μm emission of p–i–n GaNAsBi-based quantum wells (QWs) using a self-consistent calculation combined with (16×16) BAC model. Their performances are evaluated in terms of spontaneous emission rate Rsp and radiative current density Jrad. We have found that Jrad increases as function of the injected carrier density as well as the doping density. The quantum confined Stark effect on radiative current density in ideal lasers is also discussed. The radiative current density versus well width for simple and double p-GaAs/i-GaN·58yAs1-1·58yBiy/n-GaAs quantum well structures is also examined. We have obtained that Jrad increases with increase average thickness of GaNAsBi active region. The optimization of well parameters can be used as a basis for GaNAsBi-based lasers intended for optical fiber telecommunication wavelength.

Research paper thumbnail of Adsorption of Bi adatom on InAs (001) – β2 (2 × 4) and α2 (2 × 4) surface: A first principles study

Materials Science in Semiconductor Processing

Research paper thumbnail of First-principles study of atomic and electronic structure of Bi/ InP (001)-α2 (2x4) and β2 (2x4) surfaces

Materials Research Express

Research paper thumbnail of Effect of V/III ratio on the optical properties of (3 1 1)A and (3 1 1) B oriented InAlAs/InP heterostructures

Research paper thumbnail of Theoretical study of the carrier effective mass in diluted III-N-V semiconductor alloys by using 10-band k.p model

Thin Solid Films

The dependence of carrier effective mass of GaN x As 1 − x , InN x P 1 − x , InN x As 1 − x , and... more The dependence of carrier effective mass of GaN x As 1 − x , InN x P 1 − x , InN x As 1 − x , and InN x Sb 1 − x alloys on nitrogen content is investigated using a 10-band k.p model. The electron effective mass m e ⁎ at the bottom of conduction band in GaN x As 1 − x and InN x P 1 − x exhibits a gradual increase as a function of N concentration in the range 0− 1% and a decrease of x value between 1 and 5%. However, the behavior of m e ⁎ in InN x As 1 − x and InN x Sb 1 − x shows a strong decrease in all studied x-range. Our results are compared to the available data reported in the literature. On the other hand, contrary to heavy-hole effective mass m hh ⁎ , the light-hole effective mass m lh ⁎ in all studied alloys is significantly affected by nitrogen states, which modify the non-parabolicity of the LH band. The modification of the carrier effective mass affects the transport properties of the III-N-V alloys.