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This study set out to introduce the optical nonlinearities of a intense laser-driven two-dimensional quantum ring subjected to external uniform magnetic field. Inclusion of the effect of non-resonant, high-frequency THz laser radiation is realised by the laser-dressed potential, whereas the total optical absorption coefficients, total relative refractive index changes and third-harmonic generation (THG) coefficient are inferred from the scheme of compact density-matrix formalism and iterative method. Our results reveal that the laser field smoothens the antidot region of the ring that consequences with remarkable modifications in the electronic structure and correspondingly the optical response of the system. We have found that the height and location of the resonant peaks of total optical absorption coefficient, total relative refractive index changes and THG coefficient can be controlled by the externally applied fields and system parameters. The tunability of the intersubband transitions could be beneficial for practical device application relying on the electronic optical transitions.

WOS: 000458815300063, PubMed ID: 30764987, In the present work, the effect of non-resonant intense laser field on the nonlinear optical rectification and second and third harmonic generation of n-type double delta-doped GaAs quantum well is studied in detail. The energy eigenvalues and eigenfunctions of this structure are calculated within the framework of effective mass and envelope function approximations. Analytic formulas for the coefficients of nonlinear optical rectification and second and third harmonic generation are obtained using the compact-density matrix approach (CDMA) and iterative method. Based on this model, our obtained numerical results are reported as a function of incident photon energy for several values of non-resonant intense laser field. The results show that the coefficients of nonlinear optical rectification and second and third harmonic generation are strongly affected by the non-resonant intense laser field.

Within the framework of effective-mass and envelope wave function approach, using a variational method, we have investigated the binding energy of shallow-donor impurities in an asymmetrical semi-exponential quantum wells (ASEQW). The obtained numerical results show that the structure parameters (σ and, V0) lead to significant changes in the impurity binding energy. Furthermore, these results show that the hydrogenic donor impurity binding energy may be increased or decreased as a function of the impurity position in quantum well.

WOS: 000449621100040, A theoretical study of the effects of non-resonant intense laser field on the optical response in a Gaussian potential quantum well is performed in the framework of the effective mass approximation. The obtained results indicate that, the depth and range of the considered confinement potential and intense laser field intensity has a significant effect on the optical properties in Gaussian potential quantum wells. Also it was found that the laser field is more effective on the optical response in Gaussian potential quantum wells with smaller range.

In this paper, we have investigated the effects of the non-resonant intense laser field on the electronic and optical properties such as linear, nonlinear and the total optical absorption coefficient and refractive index change for transitions between two lower-lying electronic states in the GaAs-based δ -doped quantum well. Within the effective mass approximation, we calculated the eigenvalues and corresponding eigenfunctions as a function of the intense laser parameter by solving the Schrodinger equation in the laser-dressed confinement potential. The analytical expressions of the linear and third-order non-linear optical absorption coefficients and refractive index changes are obtained by using the compact-density matrix formalism. The obtained results show that the separation between ground and first excited energy levels in the δ -doped quantum well decreases in energy by the increase of the laser field intensity and this effect leads to an optical red-shift in the intersubband transitions. This behavior gives us a new degree of freedom in tunability of different device applications based on the optical transitions.

WOS: 000398055300002, We investigate theoretically the intense laser-induced optical absorption coefficients and refractive index changes in a two-dimensional quantum pseudodot system under an uniform magnetic field. The effects of non-resonant, monochromatic intense laser field upon the system are treated within the framework of high-frequency Floquet approach in which the system is supposed to be governed by a laser-dressed potential. Linear and nonlinear absorption coefficients and relative changes in the refractive index are obtained by means of the compact-density matrix approach and iterative method. The results of numerical calculations for a typical GaAs quantum dot reveal that the optical response depends strongly on the magnitude of external magnetic field and characteristic parameters of the confinement potential. Moreover, we have demonstrated that the intense laser field modifies the confinement and thereby causes remarkable changes in the linear and nonlinear optical properties of the system.

WOS: 000397696300010, In this study, the effects of electric and magnetic fields on the optical rectification and second and third harmonic generation in asymmetric double quantum well under the intense non-resonant laser field is theoretically investigated. We calculate the optical rectification and second and third harmonic generation within the compact density -matrix approach. The theoretical findings show that the influence of electric, magnetic, and intense laser fields leads to significant changes in the coefficients of nonlinear optical rectification, second and third harmonic generation. (C) 2017 Elsevier B.V. All rights reserved.

WOS: 000465001500024, In this present work a detailed theoretical study on the influence of the static electric, magnetic, and nonresonant intense THz laser fields on the nonlinear optical properties such as nonlinear optical rectification (NOR) and second harmonic generation (SHG), of a quantum well that has the Woods-Saxon potential profile. The static electric and high-frequency intense THz laser fields are applied along the growth-direction of the structure whilst the static magnetic field is applied perpendicular to them. The outcome of the numerical calculation demonstrates that, both the peak potions of the NOR and SHG coefficients exhibit a blue-shift with the increment of the static electric and magnetic fields, but their peak amplitudes increases with the magnitude of the electric field whilst decreases with the magnitude of the magnetic field. However, the peak positions of the NOR and SHG coefficients exhibit firstly a blue-shift, and then a red-shift with the increment of the laser intensity, but their peak amplitudes increases. We hope that these theoretical results will be useful for designing new optoelectronic devices with a performance tailored by the adjustment of the applied fields.

WOS: 000461957300001, A theoretical study of the effects of non-resonant intense laser field on the donor impurity binding energy in a cylindrical quantum dot with delta-doped axial potential is performed in the framework of the effective mass approximation. The obtained results indicate that, 2D impurity concentration and intense laser field intensity have a significant effect on the impurity binding energy and energy levels of electrons in the cylindrical quantum dots with delta-type axial potential.

In this present work, the effect of non-resonant, mono-chromatic intense laser field (ILF) on the linear and nonlinear optical properties of a semi-exponential quantum well (SEQW) is investigated theoretically within the effective-mass and envelope wave function approach. The bound subband energy levels and their envelope wave functions of the structure are calculated by using the diagonalization method. The optical properties of the system are obtained by using the compact-density matrix approach. The obtained numerical results show that the applied ILF and structure parameters have a significant impact on the optical properties of these structures, such as the linear, third-order nonlinear and total absorption coefficients and relative refractive index changes. Furthermore, from the findings of this study, it has been concluded that the linear and nonlinear optical properties in a SEQW under the ILF can be tuned by changing structure parameters, such as the effective range and depth of the system. © 2019 Elsevier GmbH

WOS: 000432750900015, The third-harmonic generation (THG) coefficient for a laser-driven quantum dot with an on-center Gaussian impurity under static magnetic field is theoretically investigated. Laser field effect is treated within the high-frequency Floquet approach and the analytical expression of the THG coefficient is deduced from the compact density-matrix approach. The numerical results demonstrate that the application of intense laser field causes substantial changes on the behavior of THG. In addition the position and magnitude of the resonant peak of THG coefficient is significantly affected by the magnetic field, quantum dot size and the characteristic parameters of the impurity potential.

The combined effects of electric and magnetic fields on the optical absorption coefficients and refractive index changes related to the intersubband transitions within the conduction band of asymmetric GaAs / Ga 1 - x Al x As double inverse parabolic quantum wells are studied using the effective-mass approximation and the compact density-matrix approach. The results are presented as a function of the incident photon energy for the different values of the electromagnetic fields and the structure parameters such as quantum well width and the Al concentration at the well center. It is found that the optical absorption coefficients and the refractive index changes are strongly affected not only by the magnitudes of the electric and magnetic fields but also by the structure parameters of the system.

WOS: 000451653700009, In the present study, we theoretically reported the effects of applied external fields, such as intense laser field and electric and magnetic fields, on the optical absorption coefficient and refractive index changes in the Tietz-Hua potential quantum well by the compact density-matrix approach. For this, we first calculated the subband energy levels and their corresponding electronic wave functions of the structure by solving the one-dimensional Schrodinger equation within the framework of the effective mass and envelope wave function approximations. Our theoretical results show that the optical absorption coefficient and refractive index changes in the Tietz-Hua potential quantum well are sensitive to the applied external fields. The absorption spectra in the structure can be adjusted depending on the purpose by changing the strength of the applied external fields, and these results can be used to tune and control the electronic and optical properties of the Tietz-Hua potential quantum well., Scientific Research Project Fund of Cumhuriyet University (CUBAP) [TEKNO-019], The authors are grateful to the Scientific Research Project Fund of Cumhuriyet University (CUBAP) under the project number TEKNO-019.

WOS: 000437047400036, A theoretical study of the effects of a nonresonant intense laser field on the absorption coefficients and refractive index changes for a two-level system associated with transitions from the 1S -like impurity state to the 2P(z) -like impurity state in a cylindrical quantum dot with a delta-doped axial potential is performed in the framework of the effective mass approximation. It is found that the nonresonant intense laser field and axial impurity position have obvious effects on the transition matrix elements and also on the difference between the electron densities of the states in cylindrical quantum dots, which are related to the refractive index changes and optical absorption coefficients.

WOS: 000414180500020, In this study, the effects of the electric and magnetic fields as well as structure parameter-gamma on the total absorption coefficient, including linear and third order nonlinear absorption coefficients for the optical transitions between any two subband in the Tietz-Hua quantum well have been investigated. The optical transitions were investigated by using the density matrix formalism and the perturbation expansion method. The Tietz-Hua quantum well becomes narrower (wider) when the gamma - structure parameter increases (decreases) and so the energies of the bound states will be functions of this parameter. Therefore, we can provide the red or blue shift in the peak position of the absorption coefficient by changing the strength of the electric and magnetic fields as well as the structure parameters and these results can be used to adjust and control the optical properties of the Tietz-Hua quantum well., Scientific Research Project Fund of Cumhuriyet University (CUBAP) [F-516], The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University (CUBAP) under the project number F-516.

WOS: 000410633400033, In this research, we present the effects of high-frequency intense laser field on the third-harmonic generation associated with intersubband transitions in a two-dimensional quantum pseudodot system subjected to an uniform external magnetic field. Non-resonant monochromatic laser radiation with circular polarization is considered within the framework of high-frequency Floquet approach. On the basis of the compact-density matrix approach and an iterative method, the third-harmonic generation coefficient is calculated. The results presented for a GaAs quantum dot show that: (i) the position and magnitude of the resonant peak of third-harmonic generation depend strongly on magnetic field, the chemical potential and zero-point of pseudoharmonic potential; (ii) the strength of intense laser field modifies the confinement potential which results in considerable changes in the nonlinear optical response of the system.

WOS: 000411061000002, The effect of non-resonant intense laser field on the intersubband-related optical absorption coefficient and refractive index change in the asymmetric n-type double delta-doped GaAs quantum well is theoretically investigated. The confined energy levels and corresponding wave functions of this structure are calculated by solving the Schrodinger equation in the laser-dressed confinement potential within the framework of effective mass approximation. The optical responses are reported as a function of the d-doped impurities density and the applied non-resonant intense laser field. Additionally, the calculated results also reveal that the non-resonant intense laser field can be used as a way to control the electronic and optical properties of the low dimensional semiconductor nano-structures.

WOS: 000330821200063, The effects of the intense high-frequency laser field on the optical absorption coefficients and the refractive index changes in a GaAs/GaAlAs parabolic quantum well under the applied electric field have been investigated theoretically. The electron energy levels and the envelope wave functions of the parabolic quantum well are calculated within the effective mass approximation. Analytical expressions for optical properties are obtained using the compact density-matrix approach. The numerical results show that the intense high-frequency laser field has a large effect on the optical characteristics of these structures. Also we can observe that the refractive index and absorption coefficient changes are very sensitive to the electric field in large dimension wells. Thus, this result gives a new degree of freedom in the optoelectronic device applications. (C) 2013 Elsevier B.V. All rights reserved.

WOS: 000328527800028, In this present study, we have theoretically investigated the effects of hydrostatic pressure and temperature on the nonlinear optical properties in a typical GaAs/Ga0.7Al0.3As parabolic quantum well under the intense laser field. The energy levels and wave functions are calculated using the effective mass approximation and optical properties are obtained using the compact density-matrix approach. The numerical results show that the confinement potential and the energy difference depend strongly on the intense laser field but weakly on the hydrostatic pressure and temperature. Additionally, it has been found that the linear and nonlinear optical properties in a GaAs/Ga0.7Al0.3As parabolic quantum well under the intense laser field can be tuned by changing the hydrostatic pressure and temperature. (C) 2013 Elsevier B.V. All rights reserved., Cumhuriyet University [F-399], This work was supported by the Scientific Research Project Found of Cumhuriyet University under the project number F-399.

WOS: 000323912400014, In this present study, the combined effects of intense laser field and applied electric field on the nonlinear optical absorption and refractive index change in Ga1-xInxNyAs1-y/GaAs double quantum wells are theoretically investigated within the framework of the compact density matrix approach and iterative method. The energy eigenvalues and their corresponding eigenfunctions are calculated within the effective mass approximation and the envelope wave function approach. It has been seen that the effect of the intense laser field together with an applied electric field, causes an important modification in the confined energy states of the system, mainly due to the important changes in the potential shape induced by the laser field, treated within the laser-dressed approximation. Therefore, these external fields have a great influence on the optical absorption coefficients and refractive index changes of these systems. (C) 2013 Elsevier B.V. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [COST 109T650], This research was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) for a research Grant COST 109T650.

WOS: 000394635200014, In this work, within the effective mass approximation we have performed a theoretical study of electronic states, the intersubband-related optical absorption coefficient and relative refractive index change properties in the GaAs-based double delta-doped quantum well under non-resonant intense laser field. By solving the Schrodinger equation in the laser-dressed confinement potential, We calculated eigenvalues and corresponding eigenfunctions as an intense laser parameter. We concluded that the separation between ground and first excited energy levels in the double delta-doped quantum well increases in energy by the increase of the laser field intensity and this effect leads to an optical blue-shift in intersubband transitions. Therefore a significant tunability of the optical transitions in double delta-doped quantum well can be achieved by modulating the intensity of the intense laser field. (C) 2016 Elsevier B.V. All rights reserved.

WOS: 000400556100048, We have calculated the effects of the intense laser field on the total optical absorption coefficient (the linear and third-order nonlinear) for transition between two lower-lying electronic levels in the asymmetric parabolic GaAs/ Ga1-xAlxAs quantum well. Total absorption coefficient (linear and nonlinear absorption coefficient) for the transitions between any two electronic states was calculated by using density matrix formalism and the perturbation expansion method. Our results show that the effects of intense laser field and the well dimensions on the optical transitions are more pronounced. If well center is changed to be Lc < 0 (L-c > 0), effective well width decreases (increases) and thus we can obtain the red or blue shift in the peak position of the absorption coefficient by changing the intensities of the non-resonant intense laser field as well as dimensions of the well., Scientific Research Project Fund of Cumhuriyet University (CUBAP) [F-470], The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University (CUBAP) under the project number F-470.

WOS: 000401386400032, In the present work, the effects of the non-resonant intense laser field, electric and magnetic fields on the optical properties, such as linear, third order nonlinear and the total optical absorption coefficient and refractive index changes associated with the intersubband transitions between the ground and the first excited states in the n-type double delta-doped GaAs quantum well is theoretically studied by solving the Schrodinger equation in the laser-dressed confinement potential within the framework of effective mass approximation. The analytical expressions of the linear and third-order nonlinear optical absorption coefficients and refractive index changes are obtained by using the compact-density matrix formalism. Our numerical results show that the optical absorption coefficient and refractive index change are quite sensitive to the applied external fields, such as non resonant intense laser field, electric and magnetic fields. The obtained results can be applied for the design of various optoelectronic devices based on the intersubband transitions of electrons.

WOS: 000391468200036, In this work, the effects of magnetic field, hydrostatic pressure and temperature on the linear and nonlinear optical properties in GaAs/AlxGa1-xAs symmetric double semi-V-shaped quantum well (DSVQWs) have been theoretically studied by using the compact-density matrix approach and the effective-mass approximation. Our numerical results show that the optical characteristic of these structures is strongly affected by the magnetic field, hydrostatic pressure and temperature.

Bu çalışmada, asimetrik çift kuantum kuyusunun doğrusal olmayan optik düzeltme, ikinci ve üçüncü harmonikleri üzerine Al-konsantrasyonu ve rezonans olmayan yoğun lazer alanının etkisi kompakt yoğunluk matris yaklaşımı kullanılarak teorik olarak incelenmiştir. Sonuçlar, yoğun lazer alanı ve Al-konsantrasyonun doğrusal olmayan optik düzeltme, ikinci ve üçüncü harmonikler üzerine önemli değişmelere neden olduğunu göstermektedir., In this study, the effects of a non-resonant intense laser field and the Al-concentration on the optical rectification, second and third harmonic generation in asymmetric double quantum well are investigated within the compact density matrix approach theoretically. The results show that the intense laser field and the Al-concentration lead to significant changes in the coefficients of nonlinear optical rectification, second and third harmonic generations.

WOS: 000300596000044, The effects of an intense, high-frequency laser field linearly polarized along the growth direction on the binding energy of excitons confined in a GaInNAs/GaAs quantum well is computed for different nitrogen and indium mole fractions by means of a variational technique within the effective-mass approximation. Our results show that such laser field creates an additional geometric confinement on the electronic and exciton states in the quantum well and the exciton binding energy depends on both the nitrogen and indium concentrations. (C) 2011 Elsevier B.V. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [COST 109T650], This work supported by The Scientific and Technological Research Council of Turkey (TUBITAK) for a research Grant COST 109T650.

WOS: 000291420700007, Within the framework of effective-mass approximation, we have calculated theoretically the effects of hydrostatic pressure and doping concentration on subband structure and optical transitions in modulation-doped GaAs/Al(x)Ga(1-x)As quantum well for different well widths. The electronic structure of modulation-doped quantum well under the hydrostatic pressure is determined by solving the Schrodinger and Poisson equations self-consistently. The results obtained show that intersubband transitions and the subband energy levels in the modulation-doped quantum well can be significantly modified and controlled by the well width, donor concentration and hydrostatic pressure. (C) 2011 Elsevier Ltd. All rights reserved.

WOS: 000289060100017, The effects of intense high-frequency laser field on photoionization cross-section and binding energy of shallow-donor impurities in GaAs/GaAlAs quantum dots are calculated using variational method with the effective-mass approximation. From these calculations, it has been concluded that the dependences of the impurity binding energy and photoionization cross-section on the intense laser field are very significant. (C) 2011 Elsevier B.V. All rights reserved.

WOS: 000300022700001, Using the effective-mass approximation within a variational scheme, we have calculated the diamagnetic susceptibility and binding energy of a hydrogenic donor in a quantum well under different temperatures and hydrostatic pressure conditions. Our calculation have revealed the dependence of the diamagnetic susceptibility and the impurity binding on temperature and hydrostatic pressure.

Using a variational approach we have calculated the hydrostatic pressure and temperature effects on the donor impurity related photoionization cross-section and impurity binding in GaAs/GaAlAs quantum dots Our calculations have revealed the dependence of the photoionizaton cross-section and the impurity binding on temperature and hydrostatic pressure (C) 2010 Elsevier Ltd All rights reserved

Bu çalışmada, tek parabolik kuantum kuyusunda 1s, 2s ve 2p± düzeylerindeki donor safsızlık atomunun bağlanma enerjisi, etkin kütle yaklaşımında varyasyonel olarak, kuyu genişliği ve dışarıdan uygulanan manyetik alanın bir fonksiyonu olarak hesaplamıştır. Ayrıca, GaAs/Ga1-xAlxAs tek parabolik kuantum kuyusunda hidrojenik düzeyler arasındaki kızılötesi geçişler üzerinde manyetik alanın etkisi incelenmiştir., In this study, the binding energy of the donor impurity at 1s, 2s and 2p± states in a parabolic quantum well is calculated variationally within the effective mass approximation as a function of the quantum well width and the external magnetic field. Furthermore, the effects of the magnetic field on the infrared transitions between the hydrogenic states in a parabolic quantum well under are investigated.

WOS: 000381593900018, In the present study, the effects of electric and magnetic fields on the linear and third-order nonlinear optical absorption coefficients and relative change of the refractive index in asymmetric GaAs/GaAlAs double quantum wells under intense laser fields are theoretically investigated. The electric field is oriented along the growth direction of the heterostructure while the magnetic field is taken in-plane. The intense laser field is linear polarization along the growth direction. Our calculations are made using the effective-mass approximation and the compact density-matrix approach. Intense laser effects on the system are investigated with the use of the Floquet method with the consequent change in the confinement potential of heterostructures. Our results show that the increase of the electric and magnetic fields blue-shifts the peak positions of the total absorption coefficient and of the total refractive index while the increase of the intense laser field firstly blue-shifts the peak positions and later results in their red-shifting. (C) 2016 Elsevier B.V. All rights reserved., Scientific Research Project Fund of Cumhuriyet University [TEKNO-007]; project EIA-UdeA ("Efectos de laser intenso sobre las propiedades opticas de nanoestructuras semiconductoras de InGaAsN/GaAs y GaAlAs/GaAs.") Escuela de Ingenieria de Antioquia., The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University under the project number TEKNO-007. CAD is grateful to the Colombian Agencies CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and projects: "On the way to development of new concept of nanostructure-based THz laser" and "Propiedades opticas de impurezas, excitones y moleculas en puntos cuanticos autoensamblados"), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication projects 2015-2016); and El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion, Francisco Jose de Caldas. Co-funded project EIA-UdeA ("Efectos de laser intenso sobre las propiedades opticas de nanoestructuras semiconductoras de InGaAsN/GaAs y GaAlAs/GaAs.") Escuela de Ingenieria de Antioquia.

WOS: 000383985700007, The effects of nitrogen and indium concentrations on the 1s, 2s, 2p(0) and 2p +/--like donor impurity energy states in a single Ga1-xInxNyAs1-y/GaAs quantum well (QW) are investigated by variational approach within the effective mass approximation. The results are presented as a function of the well width and the donor impurity position. It is found that the impurity binding and transition energies depend strongly on the indium concentration while depends weakly on the nitrogen concentration.

WOS: 000245999400003, Using a variational approach, we have calculated the photo-ionization cross-section of a shallow donor impurity in a quantum dot with finite and infinite potential barriers in the presence of an electric field as a function of the photon energy. Our calculations have revealed the dependence of the photodonization cross-section on the electric field, the size of the quantum dot and the impurity position.

WOS: 000232959400012, Using a variational approach, we have calculated the hydrostatic pressure and electric field effects on the donor-impurity related photoionization cross-section and impurity binding energy in GaAs/GaAlAs quantum well-wires. Both the results of impurity binding energy as a function of the impurity position and photoionization cross-section for a hydrogenic donor impurity placed at the center of the quantum well-wire as a function of the normalized photon energy in the quantum well-wire under the hydrostatic pressure and electric field which are applied to the z-direction for two different wire dimensions are presented. (c) 2005 Elsevier B.V. All rights reserved.

WOS: 000220190200007, Using a variational approach, we have calculated the impurity position dependence of the photoionization cross-section and the binding energy of a hydrogenic donor impurity in a quantum well wire in the presence of the magnetic field as a function of the photon energy. Our calculations have revealed the dependence of the photoionization cross-section and the impurity binding on the applied magnetic field, the size of the wire and the impurity position.

WOS: 000360095000019, In this present work, the effects of the structure parameters such as the right-well width and the rightbarrier height on the linear, third-order nonlinear and total absorption and refractive index changes of asymmetric double semi-V-shaped quantum well are theoretically studied by using the compact-density matrix approach and iterative method. The electronic structure of this system is obtained by solving Schrodinger equation within the framework of effective mass approximation. Numerical results are presented for a typical GaAs/AlxGa1-xAs asymmetric double semi-V-shaped quantum well. The obtained results show that the right-well width and the right-barrier height have great effects on the optical characteristics of these structures. (C) 2015 Elsevier B.V. All rights reserved.

WOS: 000361952400006, Within the effective mass approximation, the effects of the electric and intense laser fields on the binding energy and the photoionization cross-section of shallow-donor impurities in GaAs/GaAlAs parabolic quantum wires are investigated theoretically by using a variational method. The numerical results show that the electric and intense laser fields lead to significant changes in the binding energy and photoionization cross-section. (C) 2015 Elsevier B.V. All rights reserved.

WOS: 000350075500023, In the present work, the effects of the intense laser field on total optical absorption coefficient (the linear and third-order nonlinear) and total refractive index change for transition between two lower-lying electronic levels in the step-like GaAs/Ga1-xAlxAs quantum well under external electric and magnetic fields are investigated. The calculations were performed within the compact density-matrix formalism with the use of the effective mass and parabolic band approximations. The obtained results show that both total absorption coefficient and refractive index change are sensitive to the well dimensions and the effects of external fields. By changing the intensities of the electric, magnetic and non-resonant intense laser fields together with the well dimensions, we can obtain the blue or red shift, without the need for the growth of many different samples. (C) 2015 Elsevier B.V. All rights reserved., Cumhuriyet University [F-410]; Colombian Agencies: CODI-Universidad de Antioquia. (Estrategia de Sostenibilidad de la Universidad de Antioquia); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia(CAD-exclusive dedication project); EL PATRIMONIO AUTONOMO FONDO NACIONAL DE FINANCIAMIENTO PARA LA CIENCIA; LA TECNOLOGIA Y LA INNOVACION, FRANCISCO JOSE DE CALDAS; Mexican CONACYT [CB-2008-101777]; EIA-UdeA project: Efectos de laser intenso sobre las propiedades opticas de nanoestrucuras semiconductoras de InGaAsN/GaAs y GaAlAs/GaAs; Physics Depai linent of the Cumhuriyet University in Sivas, Turkey, The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University under the project number F-410. This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia. (Estrategia de Sostenibilidad 2014-2015 de la Universidad de Antioquia), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia(CAD-exclusive dedication project 2014-2015), and by EL PATRIMONIO AUTONOMO FONDO NACIONAL DE FINANCIAMIENTO PARA LA CIENCIA, LA TECNOLOGIA Y LA INNOVACION, FRANCISCO JOSE DE CALDAS. MEMR acknowledges support from Mexican CONACYT through Grant CB-2008-101777. The Escuela de Ingenieria de Antioquia co-supported EIA-UdeA project: Efectos de laser intenso sobre las propiedades opticas de nanoestrucuras semiconductoras de InGaAsN/GaAs y GaAlAs/GaAs. RLR is also grateful to the Physics Depai linent of the Cumhuriyet University in Sivas, Turkey for the support and hospitality during his research stay.

3rd International Congress on Advances in Applied Physics and Materials Science -- APR 24-28, 2013 -- Antalya, TURKEY, WOS: 000339825400011, Using the effective mass and parabolic band approximations, the binding energy of a shallow donor impurity is calculated in a GaAs-(Ga,Al)As quantum well wire of rectangular transversal section, under the combined effects of two independent axially-applied intense laser radiation fields and a static electric field oriented in the cross-section plane. The lateral size of the rectangular cross-section is assumed to be larger than 10 nm, in such a way that the uncorrelated electron motion along the x and y directions can be considered uncoupled. The impurity-related states are calculated by means of a variational procedure using a three-dimensional hydrogen-like trial wave function. The intense laser field effects are introduced via the combination of the Floquet method for the laser-modified confinement potential shape and the inclusion of a two-interaction centers model for the Coulombic coupling. It is shown that, according to the polarization of the incident radiation, the quantum well wire can evolve from a single 1D-heterostructure towards a configuration of two-well defined or four-well defined laser-induced parallel coupled quantum well wires. The obtained results also show that the binding energy is strongly dependent on the impurity position and on the strength of the intense laser field parameter., Doga Nanobiotech Inc, Mega Technol Serv Inc

WOS: 000340626600016, In the present work, total optical absorption coefficient (the linear and third-order nonlinear) and total refractive index change for transition between two first lower-lying electronic levels in the step-like GaAs/Ga1-xAlxAs quantum well under the electric and magnetic fields are investigated and also the effect of relaxation time on saturation is investigated. A compact density-matrix approach is applied to investigate optical properties. The obtained results show that both total absorption coefficient and refractive index change are sensitive to well dimensions more than external fields. With the increase of quantum well width, total absorption coefficient and refractive index change shift to lower photon energies (red shift), the magnitude of total refractive index increases significantly while total absorption coefficient is reduced. Furthermore, the electric and magnetic fields induce a blue-shift on absorption coefficient and refractive index change. (C) 2014 Elsevier B.V. All rights reserve, CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project); El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion, Francisco Jose de Caldas; Mexican CONACYT [101777]; Cumhuriyet University [F-399, F-410], This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad 2013-2014 de la Universidad de Antioquia), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2013-2014), and by El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion, Francisco Jose de Caldas. M.E.M.R. acknowledges support from Mexican CONACYT through Grant no. 101777. The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University under the project number F-399 and F-410. The work was done with the help of CENAPAD-SP, Brazil.

WOS: 000319490900011, In this study, the interband optical transitions and the binding energy of an exciton in a GaAs/Ga1-xAlxAs V-shaped quantum well (VQW) under the electric and magnetic fields are calculated. The calculations were performed within the effective mass approximation, using a variational method. It has been observed that the electric and magnetic fields provide an important effect on the electronic and optical properties in the VQW and the changes in the binding energy depend on the shape of the confinement potential. (C) 2013 Elsevier Ltd. All rights reserved.

WOS: 000313393300034, The effect of indium and nitrogen mole concentrations on the nonlinear optical properties in a Ga1-xInxNyAs1-y/GaAs single quantum well under the intense laser field is theoretically studied within the effective mass approximation and the envelope function approach. The analytical expressions of optical properties are obtained by using the compact density-matrix approach. The numerical results show that the linear, third-order nonlinear and total absorption and refractive index changes depend both on the intense laser field and on the indium and nitrogen concentrations. From the findings of this study, it has been concluded that the linear and nonlinear optical properties in a Ga1-xInxNyAs1-y/GaAs single quantum well under the intense laser field can be tuned by changing the indium and nitrogen mole fraction. (c) 2012 Elsevier B.V. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [COST 109T650]; Scientific Research Project Fund of Cumhuriyet University [F-360], This research was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) for a research Grant COST 109T650 and also was partially supported by Scientific Research Project Fund of Cumhuriyet University under the project number F-360.

Within the framework of the compact-density matrix approach and iterative method, we study theoretically the effect of electric field on the nonlinear optical rectification (NOR) and second harmonic generation (SGH) in asymmetric parabolic quantum well (APQW) under the intense laser field (ILF). The numerical results show that the electric field, and ILF lead to significant changes in the coefficients of NOR, SGH. Keywords: Nonlinear optics, intense laser field, electric field Ozet. Bu calismada yogun lazer alani altindaki asimetrik parabolik kuantum kuyusunun dogrusal olmayan optiksel kirilma ve ikinci dereceden uretim katsayilarinin uzerine elektrik alanin etkisi kompakt yogunluk matrisi yaklasimi cercevesinde teorik olarak calisilmistir.

WOS: 000303297200003, In this present work, we have investigated theoretically the effects of applied electric and magnetic fields on the linear and nonlinear optical properties in a GaAs/AlxGa1-xAs inverse parabolic quantum well for different Al concentrations at the well center. The Al concentration at the barriers was always x(max) = 0.3. The energy levels and wave functions are calculated within the effective mass approximation and the envelope function approach. The analytical expressions of optical properties are obtained by using the compact density-matrix approach. The linear, third-order nonlinear and total absorption and refractive index changes depending on the Al concentration at the well center are investigated as a function of the incident photon energy for the different values of the applied electric and magnetic fields. The results show that the applied electric and magnetic fields have a great effect on these optical quantities. (C) 2012 Elsevier B.V. All rights reserved.

WOS: 000304641400013, In this work, the effect of a non-resonant intense laser field on the optical rectification and second and third harmonic generation in a Poschl-Teller quantum well is theoretically investigated. In this regard, the coefficients of nonlinear optical rectification and second and third harmonic generation are obtained by using the compact-density matrix approach and an iterative method. Different values of the asymmetry parameters of the Poschl-Teller potential as well as intense laser field strength have been considered. Numerical results presented for a typical GaAs quantum wells show that higher-order optical effects are considerably sensitive to intense laser field and can be adjusted by a correct choice of asymmetry parameters of the potential. (C) 2012 Elsevier B.V. All rights reserved., TUBITAK (COST) [109T650]; Colombian Agency COLCIENCIAS; Colombian Agency CODI-Universidad de Antioquia [E01553]; Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia [2011-2012]; Mexican CONACYT; Colombian COLCIENCIAS; CONACYT [CB/2008-101777], We gratefully acknowledge the financial support from TUBITAK (COST) (Grant No. 109T650). C.A.D. is grateful to the Colombian Agencies COLCIENCIAS, CODI-Universidad de Antioquia (project: E01553-Propiedades Opticas no lineales en heteroestructuras semiconductoras de baja dimensionalidad (nitruros y arseniuros)), and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2011-2012). C.A.D. and M.E.M.R. wish to thank Mexican CONACYT and Colombian COLCIENCIAS for support under 2008 bilateral Grant "Estudio de propiedades opticas y electronicas en nanoestructuras y sistemas semiconductores de baja dimension". M.E.M.R. also acknowledges partial support from CONACYT through grant CB/2008-101777.

WOS: 000298219200035, In this paper, the effects of hydrostatic pressure, temperature and intense laser field on the linear and non-linear optical processes in the conduction band of a square quantum well are numerically investigated in the effective mass approximation. The analytical expressions of optical properties are obtained by using the compact density-matrix approach. The numerical results are presented for typical square GaAs/AlxGa1-xAs single quantum well system. The nonlinear optical absorption and refractive index changes depending on the hydrostatic pressure and intense laser field are investigated for two different temperature values. The results show that the intense laser field, the hydrostatic pressure and the temperature have a significant effect on the optical characteristics of these structures. (C) 2011 Elsevier B.V. All rights reserved.

WOS: 000302662700046, We perform theoretical calculations for the band structure of semiconductor superlattice under intense high-frequency laser field. In the frame of the non-perturbative approach, the laser effects are included via laser-dressed potential. Results reveal that an intense laser field creates an additional geometric confinement on the electronic states. Numerical results show that when tuning the strength of the laser field significant changes come in the electronic energy levels and density of states. (C) 2012 Elsevier B.V. All rights reserved., TUBITAK (COST) [109T650]; CODI-Universidad de Antioquia (Estrategia de Sostenibilidad Grupo de Materia Condensada-UdeA); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia; El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion Francisco Jose de Caldas [275-2011], We gratefully acknowledge the financial support from TUBITAK (COST) (Grant No. 109T650). CAD is grateful to the Colombian Agencies CODI-Universidad de Antioquia (Estrategia de Sostenibilidad Grupo de Materia Condensada-UdeA, 2011-2012), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2011-2012), and "El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion Francisco Jose de Caldas" Contract RC - No. 275-2011.