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7. Spin–Orbit and Zeeman Effects on the Electronic Properties of Single Quantum Rings: Applied Magnetic Field and Topological Defects

Author

León-González, José C., primary, Toscano-Negrette, Rafael G., additional, Morales, A. L., additional, Vinasco, J. A., additional, Yücel, M. B., additional, Sari, H., additional, Kasapoglu, E., additional, Sakiroglu, S., additional, Mora-Ramos, M. E., additional, Restrepo, R. L., additional, and Duque, C. A., additional

Published
2023
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8. Optical Properties in a ZnS/CdS/ZnS Core/Shell/Shell Spherical Quantum Dot: Electric and Magnetic Field and Donor Impurity Effects

Author

Toscano-Negrette, Rafael G., primary, León-González, José C., additional, Vinasco, Juan A., additional, Morales, A. L., additional, Koc, Fatih, additional, Kavruk, Ahmet Emre, additional, Sahin, Mehmet, additional, Mora-Ramos, M. E., additional, Sierra-Ortega, José, additional, Martínez-Orozco, J. C., additional, Restrepo, R. L., additional, and Duque, C. A., additional

Published
2023
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13. Linear and nonlinear optical properties of a single dopant in GaN conical quantum dot with spherical cap

Author

El Aouami, A., primary, Bikerouin, M., additional, Feddi, K., additional, Aghoutane, N., additional, El-Yadri, M., additional, Feddi, E., additional, Dujardin, F., additional, Radu, A., additional, Restrepo, R. L., additional, Vinasco, J. A., additional, Morales, A. L., additional, Duque, C. A., additional, and Mora-Ramos, M. E., additional

Published
2020
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14. Photoionization cross section and binding energy of single dopant in hollow cylindrical core/shell quantum dot.

Author

Feddi, E., El-Yadri, M., Dujardin, F., Restrepo, R. L., and Duque, C. A.

Subjects
PHOTOIONIZATION, IONIZATION (Atomic physics), DOPING agents (Chemistry), QUANTUM electronics, QUANTUM electrodynamics
Abstract

In this study, we have investigated the confined donor impurity in a hollow cylindrical-shell quantum dot. The charges are assumed to be completely confined to the interior of the shell with rigid walls. Within the framework of the effective-mass approximation and by using a simple variational approach, we have computed the donor binding energy as a function of the shell sizes in order to study the behavior of the electron-impurity attraction for a very small thickness. Our results show that the binding energy of a donor impurity placed at the center of cylindrical core/shell dots depends strongly on the shell size. The binding energy increases when the shell-wideness becomes smaller and shows the same behavior as in a simple cylindrical quantum dot. A special case has been studied, which corresponds to the ratio between the inner and outer radii near to one (a/b ! 1) for which our model gives a non-significant behavior of the impurity binding energy. This fact implies the existence of a critical value (a/b) for which the binding energy of the donor impurity tends to the limit value of 4 effective Rydbergs as in a 2D quantum well. We also analyse the photo-ionization cross section considering only the in-plane incident radiation polarization. We determine its behavior as a function of photon energy, shell size, and donor position. The measurement of photoionization in such systems would be of great interest to understand the optical properties of carriers in quantum dots. [ABSTRACT FROM AUTHOR]

Published
2017
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15. Effect of the magnetic field on the nonlinear optical rectification and second and third harmonic generation in double delta-doped GaAs quantum wells

Author

Martinez-Orozco, J. C., Rojas-Briseno, J. G., Rodriguez-Magdaleno, K. A., Rodriguez-Vargas, I., Mora-Ramos, M. E., Restrepo, R. L., Ungan, F., Kasapoglu, E., Duque, C. A., [Martinez-Orozco, J. C. -- Rojas-Briseno, J. G. -- Rodriguez-Magdaleno, K. A. -- Rodriguez-Vargas, I.] Univ Autonoma Zacatecas, Unidad Acad Fis, Calzada Solidaridad Esquina Con Paseo Bufa S-N, Zacatecas 98060, Zac, Mexico -- [Rojas-Briseno, J. G. -- Rodriguez-Magdaleno, K. A. -- Rodriguez-Vargas, I. -- Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias, Inst Invest Ciencias Basicas & Aplicadas, Ave Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Ungan, F.] Cumhuriyet Univ, Fac Technol, Dept Opt Engn, TR-58140 Sivas, Turkey -- [Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, Fac Sci, TR-58140 Sivas, Turkey -- [Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia, Restrepo, R. L. -- 0000-0002-0359-353X, and Martinez-Orozco, J. C. -- 0000-0001-8373-1535

Subjects
Nonlinear optical rectification, delta-doped QW, Third Harmonic Generation, Second Harmonic Generation
Abstract

WOS: 000414178500007, In this paper we are reporting the computation for the Nonlinear Optical Rectification (NOR) and the Second and Third Harmonic Generation (SHG and THG) related with electronic states of asymmetric double Si-d-doped quantum well in a GaAs matrix when this is subjected to an in-plane (x-oriented) constant magnetic field effect. The work is performed in the effective mass and parabolic band approximations in order to compute the electronic structure for the system by a diagonalization procedure. The expressions for the nonlinear optical susceptibilities, chi((2))(0), chi((2))(2 omega), and chi((3))(3 omega), are those arising from the compact matrix density formulation and stand for the NOR, SHG, and THG, respectively. This asymmetric double d-doped quantum well potential profile actually exhibits nonzero NOR, SHG, and THG responses which can be easily controlled by the in-plane (x-direction) externally applied magnetic field. In particular we find that for the chosen configuration the harmonic generation is in the far-infrared/ THz region, thus and becoming suitable building blocks for photodetectors in this range of the electromagnetic spectra., Programa de Fortalecimiento de la Calidad en Instituciones Educativas (SEP); project "Fortalecimiento y consolidacion de los PE y los CA de la DES de Ciencias Basicas de la Universidad Autonoma de Zacatecas"; Colombian Agency: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia); Colombian Agency: Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD dedication projects); CONACyT-Mexico [275399, 275402], This research was partially supported by the "Programa de Fortalecimiento de la Calidad en Instituciones Educativas (SEP)" with project "Fortalecimiento y consolidacion de los PE y los CA de la DES de Ciencias Basicas de la Universidad Autonoma de Zacatecas". This research was also partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia) and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD dedication projects 2016-2017). K. A. R.-M. and J.G. R.-B would like to acknowledges to CONACyT-Mexico for the financial support through grants 275399 and 275402.

Published
2017

16. Intense laser field-induced nonlinear optical properties of Morse quantum well

Author

Sakiroglu, SERPİL, Kasapoglu, E., Restrepo, R. L., Duque, C. A., Soekmen, I., [Sakiroglu, S. -- Soekmen, I.] Dokuz Eylul Univ, Phys Dept, Fac Sci, TR-35390 Izmir, Turkey -- [Kasapoglu, E.] Cumhuriyet Univ, Phys Dept, Fac Sci, TR-58140 Sivas, Turkey -- [Restrepo, R. L.] EIA, Envigado 055428, Colombia -- [Duque, C. A.] Univ Antioquia UdeA, Grp Mat Condensada UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Calle 70 52-21, Medellin, Colombia, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
optical absorption, Nonlinear optics, refractive index, quantum well, GaAs, Morse potential, electric field
Abstract

International Conference on Terahertz Emission, Metamaterials and Nanophotonics (TERAMETANANO) -- APR 03-10, 2016 -- Cartagena de Indias, COLOMBIA, WOS: 000398824000017, authoren This paper investigates the effects of an intense laser field and electric field on the optical properties of quantum well represented by Morse potential. The non-resonant, high-frequency intense laser effects upon the system are treated within the framework of non-perturbative approach, modifying the confinement potential associated to the heterostructure. 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. The results for a typical GaAs quantum well correspond to several configurations of the structural parameter, the strengths of the intense laser radiation, and the static electric field. Numerical results reveal the striking influence of the external fields on the magnitude and resonant peak energy positions of the optical absorption coefficients and refractive index changes. Besides, the control of intersubband optical transitions by the structure parameter seems feasible.

Published
2017

22. Refraction index modulation induced with transverse electric field in double tunnel-coupled GaAs/AlGaAs quantum wells

Author

Shumilov, A A, primary, Vinnichenko, M Ya, additional, Balagula, R M, additional, Vorobjev, L E, additional, Firsov, D A, additional, Kulagina, M M, additional, Vasil'iev, A P, additional, Duque, C A, additional, Tiutiunnyk, A, additional, Akimov, V, additional, Restrepo, R L, additional, Tulupenko, V N, additional, and Ter-Martirosyan, A L, additional

Published
2015
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23. Intense laser field-induced nonlinear optical properties of Morse quantum well.

Author

Sakiroglu, S., Kasapoglu, E., Restrepo, R. L., Duque, C. A., and Sökmen, I.

Subjects
QUANTUM wells, ATOMIC interactions, OPTICAL properties, NONLINEAR theories, NUMERICAL analysis
Abstract

authoren This paper investigates the effects of an intense laser field and electric field on the optical properties of quantum well represented by Morse potential. The non-resonant, high-frequency intense laser effects upon the system are treated within the framework of non-perturbative approach, modifying the confinement potential associated to the heterostructure. 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. The results for a typical GaAs quantum well correspond to several configurations of the structural parameter, the strengths of the intense laser radiation, and the static electric field. Numerical results reveal the striking influence of the external fields on the magnitude and resonant peak energy positions of the optical absorption coefficients and refractive index changes. Besides, the control of intersubband optical transitions by the structure parameter seems feasible. [ABSTRACT FROM AUTHOR]

Published
2017
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24. Background impurities in Si0.8 Ge0.2/Si/Si0.8 Ge0.2 n-type δ-doped QW.

Author

Tulupenko, V., Duque, C. A., Morales, A. L., Tiutiunnyk, A., Demediuk, R., Dmytrychenko, T., Fomina, O., Akimov, V., Restrepo, R. L., and Mora‐Ramos, M. E.

Subjects
METAL inclusions, QUANTUM wells, IONIZATION (Atomic physics), BINDING energy, SEMICONDUCTOR doping
Abstract

Additional (residual) impurities in the barriers change the energy profile of a quantum well. This means that they alter the ionization energy for the impurity delta layer situated within the quantum well. In turn, this is accompanied by the change of a V-shaped quantum well created by ionization of the delta layer. All of this is the subject of studies presented in this article. It has been shown that the most dramatic are the changes in the difference between the space-quantized energy levels for an edge-doped quantum well. [ABSTRACT FROM AUTHOR]

Published
2017
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26. Impurity-Related Nonlinear Optical Absorption in Delta-Doped Quantum Rings.

Author

RESTREPO, R. L., MARTÍNEZ-OROZCO, J. C., BARSEGHYAN, M. G., MORA-RAMOS, M. E., and DUQUE, C. A.

Subjects
*LIGHT absorption, *NONLINEAR optics, *BINDING energy, *THOMAS-Fermi approximation, *OPTICAL spectra
Abstract

Using a variational procedure within the effective mass approximation, we have calculated the hydrogenic impurity binding energy as well as the impurity-related nonlinear optical absorption in a single quantum ring with axial n-type delta-doping. The delta-like potential along the z-direction is analytically modeled with a Hartree-like confining profile fitted to a one-dimensional Thomas-Fermi-based potential in the local density approximation. Both on-center and on-edge impurity positions are considered and the energies of the impurity states are examined as functions of the vertical size of the ring. It is found that the effect of changes in the geometry of the quantum ring leads to a shifting of the resonant peaks of the intra-band optical spectrum. [ABSTRACT FROM AUTHOR]

Published
2014
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28. Linear and nonlinear optical properties in the terahertz regime for multiple-step quantum wells under intense laser field: Electric and magnetic field effects

Author

J.P. González-Pereira, R.L. Restrepo, Alvaro Morales, E. Kasapoglu, C.A. Duque, [Restrepo, R. L. -- Gonzalez-Pereira, J. P.] Univ EIA, Envigado 055428, Colombia -- [Kasapoglu, E.] Cumhuriyet Univ, Fac Sci, Dept Phys, TR-58140 Sivas, Turkey -- [Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
Electric and magnetic fields, Terahertz radiation, Multiple-step quantum wells, Physics::Optics, 02 engineering and technology, Electron, 01 natural sciences, law.invention, Inorganic Chemistry, law, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Wave function, Spectroscopy, Quantum well, 010302 applied physics, Physics, Linear optical properties, Organic Chemistry, Intense laser field, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Magnetic field, Second and third harmonic generation, Atomic physics, 0210 nano-technology, Refractive index
Abstract

WOS: 000453499500082, We present a theoretical study on the linear and nonlinear optical properties in AlrGa1-rAs/GaAs asymmetric multiple step quantum wells (AMSQW) under the effects of a non-resonant intense laser field (ILF), electric, and magnetic field. Calculations are for the linear optical absorption and refractive index relative changes combined with the second and third harmonic generation. The potential profile is constructed as a function of the Aluminum concentration, so that the heterostructure has four steps of different concentration, width and height. The energy levels and corresponding wavefunctions are obtained by solving the Schordinger equation, for an electron, in the envelope function approach, with parabolic bands, and the effective mass approximations. The results show that variations in ILF, electric field and magnetic field have significant influences on the magnitude and peak energy positions of the SHG and THG coefficients. Therefore, we can conclude that the effects of ILF, electric and magnetic fields can be used to tune and control the SHG and THG in the range of the terahertz electromagnetic spectrurn., CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia); CODI-Universidad de Antioquia (project : "Efectos opticos intersubbanda, no lineales de segundo orden y dispersion Raman, en sistemas asimetricos de pozos cuanticos acoplados"); CODI-Universidad de Antioquia (project: "Efectos de capas delta dopadas en pozos cuanticos como fotodetectores en el infrarrojo"); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD exclusive dedication project 2018-2019); Universidad EIA; Universidad de Antioquia; Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (ALM exclusive dedication project 2018-2019), This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and projects: "Efectos opticos intersubbanda, no lineales de segundo orden y dispersion Raman, en sistemas asimetricos de pozos cuanticos acoplados" and "Efectos de capas delta dopadas en pozos cuanticos como fotodetectores en el infrarrojo") and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD exclusive dedication project 2018-2019 and ALM exclusive dedication project 2018-2019). The authors are grateful to the Universidad EIA and Universidad de Antioquia for its financial support through the EIA-UdeA-UdeM-project "Generacion de segundo armonico, rectificacion optica y dispersion Raman entre estados electronicos en pozos cuanticos acoplados". RLR and JPGP are grateful to Semillero de Investigacion Universidad EIA "Nanoestructuras Semiconductoras".

Published
2018
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29. Second and third harmonic generation associated to infrared transitions in a Morse quantum well under applied electric and magnetic fields

Author

E. Kasapoglu, R.L. Restrepo, Serpil Sakiroglu, C.A. Duque, F. Ungan, Alvaro Morales, [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Kasapoglu, E.] Cumhuriyet Univ, Phys Dept, TR-58140 Sivas, Turkey -- [Sakiroglu, S.] Dokuz Eylul Univ, Phys Dept, TR-35160 Buca Izmir, Turkey -- [Ungan, F.] Cumhuriyet Univ, Fac Technol, Dept Opt Engn, TR-58140 Sivas, Turkey -- [Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Grp Mat Condensada UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Calle 70 52-21, Medellin, Colombia, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
010302 applied physics, Physics, Electric and magnetic fields, Infrared transitions, 02 engineering and technology, Electron, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Schrödinger equation, Magnetic field, symbols.namesake, Effective mass (solid-state physics), Quantum mechanics, 0103 physical sciences, Bound state, symbols, Morse potential, Second and third harmonic generation, 0210 nano-technology, Wave function, Quantum well
Abstract

WOS: 000411546800020, The effects of electric and magnetic fields on the second and third harmonic generation coefficients in a Morse potential quantum well are theoretically studied. The energy levels and corresponding wave functions are obtained by solving the Schrodinger equation for the electron in the parabolic band scheme and effective mass approximations and the envelope function approach. The results show that both the electric and the magnetic fields have significant influence on the magnitudes and resonant peak energy positions of the second and third harmonic generation responses. In general, the Morse potential profile becomes wider and shallower as gamma-parameter increases and so the energies of the bound states will be functions of this parameter. Therefore, we can conclude that the effects of the electric and magnetic fields can be used to tune and control the optical properties of interest in the range of the infrared electromagnetic spectrum. (C) 2017 Elsevier B.V. All rights reserved., CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (ALM); Universidad EIA; Universidad de Antioquia, This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia) and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD and ALM exclusive dedication project 2016-2017). CAD and RLR are grateful to Universidad EIA and Universidad de Antioquia for financial support through the EIA-UdeA-UdeM-projects "Desarrollo de fotodetectores en el infrarrojo usando pozos cuanticos ajustables con dopamiento delta dentro del pozo".

Published
2017
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30. Effects of electromagnetic fields on the nonlinear optical properties of asymmetric double quantum well under intense laser field

Author

Hüseyin Sari, Ismail Sokmen, R.L. Restrepo, C.A. Duque, Fatih Ungan, U. Yesilgul, M.E. Mora-Ramos, J.C. Martínez-Orozco, [Yesilgul, U. -- Ungan, F.] Cumhuriyet Univ, Fac Technol, Dept Opt Engn, TR-58140 Sivas, Turkey -- [Sari, H.] Cumhuriyet Univ, Dept Primary, Fac Educ, TR-58140 Sivas, Turkey -- [Martinez-Orozco, J. C.] Univ Autonoma Zacatecas, Unidad Acad Fis, Calzada Solidaridad Esquina Con Paseo La Bufa S-N, Zacatecas 98060, Zac, Mexico -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Ave Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Duque, C. A.] Univ Antioquia UdeA, Grp Mat Condensada UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Calle 70 52-21, Medellin, Colombia -- [Sokmen, I.] Dokuz Eylul Univ, Dept Phys, Fac Sci, TR-35160 Izmir, Turkey, Martinez-Orozco, J. C. -- 0000-0001-8373-1535, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
Electromagnetic field, Field (physics), Electric and magnetic fields, Physics::Optics, General Physics and Astronomy, 02 engineering and technology, Nonlinear optical properties, Asymmetric double quantum well, 01 natural sciences, law.invention, Nonlinear optical, Optical rectification, Optics, Rectification, law, 0103 physical sciences, High harmonic generation, Physical and Theoretical Chemistry, 010302 applied physics, Physics, business.industry, Intense laser field, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Laser, Magnetic field, Quantum electrodynamics, 0210 nano-technology, business
Abstract

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.

Published
2017
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31. Electron Raman scattering in a double quantum well tuned by an external nonresonant intense laser field

Author

R.L. Restrepo, A. Tiutiunnyk, Alvaro Morales, M.E. Mora-Ramos, C. M. Duque, J.C. Martínez-Orozco, E. Kasapoglu, C.A. Duque, Fatih Ungan, [Tiutiunnyk, A. -- Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Av Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Tiutiunnyk, A. -- Morales, A. L. -- Duque, C. M. -- Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Ungan, F.] Cumhuriyet Univ, Dept Opt Engn, Fac Technol, TR-58140 Sivas, Turkey -- [Martinez-Orozco, J. C.] Univ Autonoma Zacatecas, Unidad Acad Fis, Calzada Solidaridad Esquina Paseo Bufa S-N, Zacatecas 98060, Zac, Mexico -- [Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, Fac Sci, TR-58140 Sivas, Turkey, Restrepo, R. L. -- 0000-0002-0359-353X, Tiutiunnyk, Anton -- 0000-0003-1692-5561, and Martinez-Orozco, J. C. -- 0000-0001-8373-1535

Subjects
Raman scattering, 02 engineering and technology, Electron, 010402 general chemistry, 01 natural sciences, Light scattering, law.invention, Inorganic Chemistry, symbols.namesake, Optics, Effective mass (solid-state physics), law, Quantum well, Physics::Atomic Physics, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Spectroscopy, Physics, business.industry, Organic Chemistry, Intense laser field, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Atomic electron transition, symbols, Atomic physics, 0210 nano-technology, business, Raman spectroscopy
Abstract

WOS: 000394635200076, In this work we shall present a study of inelastic light scattering involving inter-subband electron transitions in coupled GaAs-(Ga,AI)As quantum wells. Calculations include the electron related Raman differential cross section and Raman gain. The effects of an external nonresonant intense laser field are used in order to tune these output properties. The confined electron states will be described by means of a diagonalization procedure within the effective mass and parabolic band approximations. It is shown that the application of the intense laser field can produce values of the intersubband electron Raman gain above 400 cm(-1). The system proposed here is an alternative choice for the development of Al chi Ga1-chi As semiconductor laser diodes that can be tuned via an external nonresonant intense laser field. (C) 2017 Elsevier B.V. All rights reserved., Colombian Agencies: CODI-; Mexican PRODEP for a Posdoctoral Grant [09/2016-08/2017]; Universidad EIA; Universidad de Antioquia through the EIA-UdeA-UdeM-project "Propiedades Opto-electronicas de sistemas altamente confinados: Una aproximaciOn teorica"; Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD and ALM-exclusive dedication projects 2016-2017), This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and projects: "Propiedades opticas de impurezas, excitones y moleculas en puntos cuanticos autoensamblados" and "On the way to development of new concept of nanostructure-based THz laser") and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD and ALM-exclusive dedication projects 2016-2017). AT thanks Mexican PRODEP for a Posdoctoral Grant 09/2016-08/2017. CAD and RLR are grateful to Universidad EIA and Universidad de Antioquia for financial support through the EIA-UdeA-UdeM-project "Propiedades Opto-electronicas de sistemas altamente confinados: Una aproximaciOn teorica".

Published
2017
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32. Optical coefficients in a semiconductor quantum ring: Electric field and donor impurity effects

Author

M.E. Mora-Ramos, R.L. Restrepo, Ruben E. Acosta, J.H. Ojeda, C. M. Duque, E. Kasapoglu, Alvaro Morales, C.A. Duque, [Duque, C. M. -- Acosta, Ruben E. -- Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Ave Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Ojeda, J. H.] Univ Pedag & Tecnol Colombia, Grp Fis Mat, Tunja, Colombia -- [Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey, Restrepo, R. L. -- 0000-0002-0359-353X, and OJEDA SILVA, JUDITH HELENA -- 0000-0001-7004-2984

Subjects
02 engineering and technology, Electron, 01 natural sciences, Inorganic Chemistry, Adiabatic theorem, symbols.namesake, Effective mass (solid-state physics), Quantum rings, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Wave function, Spectroscopy, 010302 applied physics, Condensed matter physics, Optical absorption, Chemistry, Organic Chemistry, Quantum-confined Stark effect, Second harmonic generation, 021001 nanoscience & nanotechnology, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Optical phase space, Quantum dot, symbols, Donor impurity, Atomic physics, 0210 nano-technology, Hamiltonian (quantum mechanics)
Abstract

WOS: 000386644500026, The electron states in a two-dimensional quantum dot ring are calculated in the presence of a donor impurity atom under the effective mass and parabolic band approximations. The effect of an externally applied electric field is also taken into account. The wavefunctions are obtained via the exact diagonalization of the problem Hamiltonian using a 2D expansion within the adiabatic approximation. The impurity-related optical response is analyzed via the optical absorption, relative refractive index change and the second harmonics generation. The dependencies of the electron states and these optical co-efficients with the changes in the configuration of the quantum ring system are discussed in detail. (C) 2016 Elsevier B.V. All rights reserved.

Published
2016
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33. Nonlinear optical rectification and second-harmonic generation in a semi-parabolic quantum well under intense laser field: Effects of electric and magnetic fields

Author

M.E. Mora-Ramos, J.C. Martínez-Orozco, R.L. Restrepo, F. Ungan, E. Kasapoglu, C.A. Duque, [Ungan, F. -- Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Martinez-Orozco, J. C. -- Restrepo, R. L. -- Duque, C. A.] Univ Antioquia UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Grp Mat Condensada UdeA, Medellin, Colombia -- [Martinez-Orozco, J. C.] Univ Autonoma Zacatecas, Unidad Acad Fis, Zacatecas 98060, Zac, Mexico -- [Restrepo, R. L.] Escuela Ingn Antioquia, Envigado, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Fac Ciencias, Cuernavaca 62209, Morelos, Mexico, Restrepo, R. L. -- 0000-0002-0359-353X, Martinez-Orozco, J. C. -- 0000-0001-8373-1535, and Mora-Ramos, Miguel Eduardo -- 0000-0002-6232-9958

Subjects
Physics, Nonlinear optics, Second-harmonic generation, Field (physics), Intense laser field, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Condensed Matter Physics, Laser, law.invention, Magnetic field, law, Quantum mechanics, High harmonic generation, Quantum well, General Materials Science, Electrical and Electronic Engineering, Atomic physics, Wave function
Abstract

WOS: 000357233800004, The effects of electric and magnetic fields on the nonlinear optical rectification and second harmonic generation coefficients related with intersubband transitions in a semi-parabolic quantum well under intense laser field are theoretically studied. The energy levels and corresponding wave functions are obtained by solving the conduction band Schrodinger-like equation in the parabolic approximation and the envelope function approach. Numerical calculations are presented for a typical GaAs/Ga1-xAlxAs quantum well. The results show that both the non-resonant intense laser field and the static external fields have significant influences on the magnitude and resonant peak energy positions of the coefficients under study. (C) 2015 Elsevier Ltd. All rights reserved.

Published
2015
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34. Intersubband optical absorption coefficients and refractive index changes in a graded quantum well under intense laser field: Effects of hydrostatic pressure, temperature and electric field

Author

Fatih Ungan, R.L. Restrepo, C.A. Duque, M.E. Mora-Ramos, Alvaro Morales, [Ungan, F.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Restrepo, R. L. -- Mora-Ramos, M. E. -- Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensade UdeA, Medellin, Colombia -- [Restrepo, R. L.] Escuela Ingn Antioquia, Medellin 7516, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Fac Ciencias, Cuernavaca 62209, Morelos, Mexico, Restrepo, R. L. -- 0000-0002-0359-353X, and Mora-Ramos, Miguel Eduardo -- 0000-0002-6232-9958

Subjects
Physics, Field (physics), Condensed matter physics, business.industry, Hydrostatic pressure, Nonlinear optical property, Intense laser field, Condensed Matter Physics, Laser, Electronic, Optical and Magnetic Materials, law.invention, Optics, law, Electric field, Graded quantum well, Electrical and Electronic Engineering, business, Wave function, Refractive index, Quantum well, Envelope (waves)
Abstract

WOS: 000329116900005, The effects of hydrostatic pressure, temperature, and electric field on the optical absorption coefficients and refractive index changes associated with intersubband transition in a typical GaAs/Ga0.7Al0.3As graded quantum well under intense laser field have been investigated theoretically. The electron energy eigenvalues and the corresponding eigenfunctions of the graded quantum well are calculated within the effective mass approximation and envelope wave function approach. The analytical expressions of the optical properties are obtained using the compact density-matrix approach and the iterative method. The numerical results show that the linear and nonlinear optical properties depend strongly on the intense laser field and electric field but weakly on the hydrostatic pressure and temperature. Additionally, it has been found that the electronic and optical properties in a GaAs/Ga0.7Al0.3As graded quantum well under the intense laser field can be tuned by changing these external inputs. Thus, these results give a new degree of freedom in the devices applications. (C) 2013 Elsevier B.V. All rights reserved., 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; Escuela de Ingenieria de Antioquia; Efectos de lAser intenso sobre las propiedades opticas de nanoestrucuras semiconductoras de InGaAsN/GaAs y GaAlAs/GaAs; Mexican CONACYT [101777]; Cumhuriyet University [F-399], 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, 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. MEMR 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. The work was done with the help of CENAPAD-SP, Brazil.

Published
2014
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35. Donor Impurity-Related Optical Absorption in GaAs Elliptic-Shaped Quantum Dots

Author

Huynh V. Phuc, C.A. Duque, M. A. Londoño, R.L. Restrepo, M.E. Mora-Ramos, J.H. Ojeda, E. Kasapoglu, Alvaro Morales, [Londono, M. A.] Univ Antioquia UdeA, Inst Matemat, Fac Ciencias Exactas & Nat, Calle 70 52-21, Medellin, Colombia -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Ojeda, J. H.] Univ Pedag & Tecnol Colombia, Grp Fis & Mat, Tunja, Colombia -- [Huynh Vinh Phuc] Dong Thap Univ, Div Theoret Phys, Dong Thap, Vietnam -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Av Univ 1001, Cuernavaca 62209, Mor, Mexico -- [Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, Fac Sci, TR-58140 Sivas, Turkey -- [Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Grp Mat Condensada UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Calle 70 52-21, Medellin, Colombia, Phuc, Huynh V. -- 0000-0001-8063-0923, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
Materials science, Condensed matter physics, Article Subject, Quantum-confined Stark effect, GaAs, Absorción óptica, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Effective mass (solid-state physics), Quantum dot, Impurity, Electric field, 0103 physical sciences, Electro-absorption modulator, lcsh:Technology (General), Puntos cuánticos, lcsh:T1-995, General Materials Science, 010306 general physics, 0210 nano-technology, Adiabatic process, Wave function
Abstract

WOS: 000398405000001, The conduction band and electron-donor impurity states in elliptic-shaped GaAs quantum dots under the effect of an externally applied electric field are calculated within the effective mass and adiabatic approximations using two different numerical approaches: a spectral scheme and the finite element method. The resulting energies and wave functions become the basic information needed to evaluate the interstate optical absorption in the system, which is reported as a function of the geometry, the electric field strength, and the temperature., Vietnam National Foundation for Science and Technology Development (NAFOSTED) [103.01-2015.93]; Migracion Sismica Pre-Apilado en Profundidad por Extrapolacion de Campos de Onda Utilizando Computacion de Alto Desempeno para Datos Masivos en Zonas Complejas [111553130555], This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant no. 103.01-2015.93. The authors are grateful to the Colombian Agencies CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia) and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (C.A. Duque and A.L. Morales Exclusive Dedication Projects 2016-2017). M.A. Londono is grateful to Colciencias-Ecopetrol for financial support through the project Migracion Sismica Pre-Apilado en Profundidad por Extrapolacion de Campos de Onda Utilizando Computacion de Alto Desempeno para Datos Masivos en Zonas Complejas (Code 111553130555).

Published
2017

36. The effects of the electric and intense laser field on the binding energies of donor impurity states (1s and 2p(+/-)) and optical absorption between the related states in an asymmetric parabolic quantum well

Author

R.L. Restrepo, Ismail Sokmen, E. Kasapoglu, Serpil Sakiroglu, C.A. Duque, M.E. Mora-Ramos, [Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Sakiroglu, S. -- Sokmen, I.] Dokuz Eylul Univ, Dept Phys, TR-35160 Izmir, Turkey -- [Restrepo, R. L.] Univ EIA, Medellin, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Ave Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Duque, C. A.] Univ Antioquia UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
Field (physics), 02 engineering and technology, Electron, 01 natural sciences, Inorganic Chemistry, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Absorption (electromagnetic radiation), Spectroscopy, Shallow donor, Quantum well, 010302 applied physics, Chemistry, Optical absorption, Organic Chemistry, Quantum-confined Stark effect, Asymmetric parabolic quantum well, Intense laser field, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Impurity binding energy, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Excited state, Atomic physics, 0210 nano-technology
Abstract

WOS: 000386644500050, We have calculated the effects of electric and intense laser fields on the binding energies of the ground and some excited states of conduction electrons coupled to shallow donor impurities as well as the total optical absorption coefficient for transitions between 1s and 2p(+/-) electron-impurity states in a asymmetric parabolic GaAs/Ga1-x AlxAs quantum well. The binding energies were obtained using the effective-mass approximation within a variational scheme. Total absorption coefficient (linear and nonlinear absorption coefficient) for the transitions between any two impurity states were calculated from first- and third-order dielectric susceptibilities derived within a perturbation expansion for the density matrix formalism. Our results show that the effects of the electric field, intense laser field, and the impurity location on the binding energy of 1s-impurity state are more pronounced compared with other impurity states. If the well center is changed to be L-c0), the effective well width decreases (increases), and thus we can obtain the red or blue shift in the resonant peak position of the absorption coefficient by changing the intensities of the electric and non-resonant intense laser field as well as dimensions of the well and impurity positions. (C) 2016 Elsevier B.V. All rights reserved., Colombian Agency: Universidad de Antioquia; Colombian Agency: project: "Propiedades opticas de impurezas, excitones y moleculas en puntos cuanticos autoensamblados", Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project); Colombian Agency: project: "On the way to development of new concept of nanostructure-based THz laser"), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project); Colombian Agency: El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion, Francisco Jose de Caldas, This research was partially supported by Colombian Agencies: Universidad de Antioquia and projects: "Propiedades opticas de impurezas, excitones y moleculas en puntos cuanticos autoensamblados" and "On the way to development of new concept of nanostructure-based THz laser"), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2015-2016), El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Tecnologia y la Innovacion, Francisco Jose de Caldas.

Published
2016

37. Linear and nonlinear optical properties in an asymmetric double quantum well under intense laser field: Effects of applied electric and magnetic fields

Author

E. Kasapoglu, F. Ungan, E.B. Al, R.L. Restrepo, M.E. Mora-Ramos, J.C. Martínez-Orozco, U. Yesilgul, C.A. Duque, [Yesilgul, U. -- Ungan, F.] Cumhuriyet Univ, Fac Technol, Dept Opt Engn, TR-58140 Sivas, Turkey -- [Al, E. B. -- Kasapoglu, E.] Cumhuriyet Univ, Fac Sci, Dept Phys, TR-58140 Sivas, Turkey -- [Martinez-Orozco, J. C.] Univ Autonoma Zacatecas, Unidad Acad Fis, Zacatecas 98060, ZAC, Mexico -- [Restrepo, R. L.] EIA, Envigado 055428, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Fac Ciencias, Ave Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia, Restrepo, R. L. -- 0000-0002-0359-353X, and Martinez-Orozco, J. C. -- 0000-0001-8373-1535

Subjects
Floquet theory, Field (physics), Electric and magnetic fields, 02 engineering and technology, Optical field, Nonlinear optical properties, Asymmetric double quantum well, 01 natural sciences, law.invention, Inorganic Chemistry, Optics, law, Electric field, 0103 physical sciences, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, 010306 general physics, Spectroscopy, Physics, business.industry, Linear polarization, Organic Chemistry, Intense laser field, 021001 nanoscience & nanotechnology, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Magnetic field, Atomic physics, 0210 nano-technology, business, Refractive index
Abstract

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.

Published
2016

38. The effects of intense laser field and applied electric and magnetic fields on optical properties of an asymmetric quantum well

Author

C.A. Duque, Alvaro Morales, M.E. Mora-Ramos, E. Kasapoglu, Fatih Ungan, R.L. Restrepo, [Restrepo, R. L. -- Ungan, F. -- Kasapoglu, E.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Restrepo, R. L.] Escuelade Ingn Antioquia, Envigado 055428, Colombia -- [Restrepo, R. L. -- Morales, A. L. -- Duque, C. A.] Univ Antioquia UdeA, Grp Mat Condensada UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Medellin, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Fac Ciencias, Cuernavaca 62209, Morelos, Mexico, Restrepo, R. L. -- 0000-0002-0359-353X, and Mora-Ramos, Miguel Eduardo -- 0000-0002-6232-9958

Subjects
Physics, Field (physics), Electric and magnetic fields, Quantum-confined Stark effect, Optical field, Nonlinear optical properties, Intense laser field, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Magnetic field, Magnetization, Quantum mechanics, Electric field, Asymmetric single quantum well, Electric potential, Electrical and Electronic Engineering, Atomic physics, Quantum well
Abstract

WOS: 000346845200030, This paper presents the results of the theoretical study of the effects of non resonant intense laser field and electric and magnetic fields on the optical properties (the linear and third order nonlinear refractive index and absorption coefficients) in an asymmetric quantum well. The electric field and intense laser field are applied along the growth direction of the asymmetric quantum well and the magnetic field is oriented perpendicularly. To calculate the energy and the wave functions of the electron in the asymmetric quantum well, the effective mass approximation and the method of envelope wave function are used. The asymmetric quantum well is constructed by using different aluminium concentrations in both right and left barriers. The confinement in the quantum well is changed drastically by either the effect of electric and magnetic fields or by the application of intense laser field. The optical properties are calculated using the compact density matrix approach. The results show that the effect of the intense laser field competes with the effects of the electric and magnetic fields. Consequently, peak position shifts to lower photon energies due to the effect of the intense laser field and it shifts to higher photon energies by the effects of electric and magnetic fields. In general, it is found that the concentration of aluminum, electric and magnetic fields and intense laser field are external agents that modify the optical responses in the asymmetric quantum well. (C) 2014 Elsevier B.V. All tights reserved., Scientific Research Project Fund of Cumhuriyet University [F-399, F-410]; CODI-Universidad de Antioquia; 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; Mexican CONACYT [CB-2008-101777]; Escuela de lngenieria de Antioquia; EIA-UdeA, The authors are grateful to The Scientific Research Project Fund of Cumhuriyet University under the projects number F-399 and 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 lngenieria 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 Department of the Cumhuriyet University in Sivas-Turkey for the support and hospitality during his research stay.

Published
2015

39. Intense laser field effects on a Woods-Saxon potential quantum well

Author

E. Kasapoglu, R.L. Restrepo, C.A. Duque, Fatih Ungan, V. Akimov, V. Tulupenko, Alvaro Morales, [Restrepo, R. L.] Escuela Ingn Antioquia, Envigado 055428, Colombia -- [Morales, A. L. -- Akimov, V. -- Tulupenko, V. -- Duque, C. A.] Univ Antioquia UdeA, Inst Fis, Fac Ciencias Exactas & Nat, Grp Mat Condensada UdeA, Medellin, Colombia -- [Kasapoglu, E. -- Ungan, F.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Akimov, V. -- Tulupenko, V.] Donbass State Engn Acad, Dept Phys, UA-84313 Kramatorsk, Ukraine, Akimov, Volodymyr -- 0000-0001-9014-3539, and Restrepo, R. L. -- 0000-0002-0359-353X

Subjects
Physics, Condensed matter physics, Field (physics), Electric and magnetic fields, Optical transitions, Electron, Optical field, Intense laser field, Condensed Matter Physics, Magnetic field, Quantum electrodynamics, Electric field, General Materials Science, Woods–Saxon potential, Woods-Saxon potential quantum well, Electrical and Electronic Engineering, Wave function, Quantum well
Abstract

WOS: 000366876100025, This paper presents the results of the theoretical study of the effects of non-resonant intense laser field and electric and magnetic fields on the optical properties in an quantum well (QW) make with Woods Saxon potential profile. The electric field and intense laser field are applied along the growth direction of the Woods Saxon quantum well and the magnetic field is oriented perpendicularly. To calculate the energy and the wave functions of the electron in the Woods Saxon quantum well, the effective mass approximation and the method of envelope wave function are used. The confinement in the Woods Saxon quantum well is changed drastically by the application of intense laser field or either the effect of electric and magnetic fields. The optical properties are calculated using the compact density matrix. (C) 2015 Elsevier Ltd. All rights reserved., Escuela de Ingenieria de Antioquia co; 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); PATRIMONIO AUTONOMO FONDO NACIONAL DE FINANCIAMIENTO PARA LA CIENCIA, LA TECNOLOGIA Y LA INNOVACION, FRANCISCO JOSE DE CALDAS, 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. 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.

Published
2015

40. Combined effects of intense laser field, electric and magnetic fields on the nonlinear optical properties of the step-like quantum well

Author

R.L. Restrepo, Hüseyin Sari, M.E. Mora-Ramos, E. Kasapoglu, Ismail Sokmen, U. Yesilgul, F. Ungan, C.A. Duque, [Kasapoglu, E. -- Restrepo, R. L. -- Ungan, F. -- Yesilgul, U. -- Sari, H.] Cumhuriyet Univ, Dept Phys, TR-58140 Sivas, Turkey -- [Duque, C. A. -- Restrepo, R. L.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Medellin, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Fac Ciencias, Cuernavaca, Morelos, Mexico -- [Restrepo, R. L.] EIA, Medellin, Colombia -- [Sokmen, I.] Dokuz Eylul Univ, Dept Phys, TR-35160 Izmir, Turkey, Restrepo, R. L. -- 0000-0002-0359-353X, and Mora-Ramos, Miguel Eduardo -- 0000-0002-6232-9958

Subjects
Physics, Step-like quantum well, business.industry, Electric and magnetic fields, Quantum-confined Stark effect, Nonlinear optical property, Intense laser field, Condensed Matter Physics, Laser, law.invention, Magnetic field, Nonlinear system, Effective mass (solid-state physics), Optics, law, Attenuation coefficient, General Materials Science, Atomic physics, business, Refractive index, Quantum well
Abstract

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.

Published
2015

41. Effect of applied electric field on the nonlinear optical properties of modulation-doped GaAs/AlxGa1-x As double quantum well

Author

R.L. Restrepo, Fatih Ungan, M.E. Mora-Ramos, J.C. Martínez-Orozco, C.A. Duque, [Ungan, F.] Cumhuriyet Univ, Fac Technol, Dept Opt Engn, TR-58140 Sivas, Turkey -- [Martinez-Orozco, J. C.] Univ Autonoma Zacatecas, Unidad Acad Fis, Solidaridad Esquina Paseo Bufa S-N, Zacatecas 98060, Zac, Mexico -- [Restrepo, R. L.] Univ EIA, Envigado 055428, Colombia -- [Mora-Ramos, M. E.] Univ Autonoma Estado Morelos, Inst Invest Ciencias Basicas & Aplicadas, Ctr Invest Ciencias, Av Univ 1001, Cuernavaca 62209, Morelos, Mexico -- [Duque, C. A.] Univ Antioquia UdeA, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada UdeA, Calle 70 52-21, Medellin, Colombia, Restrepo Arango, Ricardo Leon -- 0000-0002-0359-353X, and Martinez-Orozco, J. C. -- 0000-0001-8373-1535

Subjects
010302 applied physics, Coupling, X-ray absorption spectroscopy, Materials science, Relative refractive index change, Self-consistent method, Doping, Absorption coefficient, 02 engineering and technology, Modulation-doped QW, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Molecular physics, Modulation, Electric field, Attenuation coefficient, 0103 physical sciences, General Materials Science, Electrical and Electronic Engineering, 0210 nano-technology, Absorption (electromagnetic radiation), Refractive index
Abstract

WOS: 000463848000012, In the present study, the effects of varying doping concentration and applied electric field on the intersubband-related optical absorption and relative refractive index change coefficients in modulation-doped GaAs/AlxGa1-x As double quantum wells are theoretically investigated. The allowed energy levels and the corresponding wave-functions are calculated by solving the Schrodinger and Poisson equations self-consistently within the framework of the effective-mass and parabolic band approximations. The optical coefficients are evaluated using the compact density matrix formalism within an iterative procedure. The numerical results are presented for two different doping concentration and several values of the electric field. They show that both the peak position and the magnitude of the calculated total optical absorption coefficients and refractive index changes are significantly affected by the applied electric field and the doping concentration. The treatment is suitable to consider the general problem with different wells and barrier sizes, although the barrier width should preferably be small enough as to allow for an effective inter-well coupling., Universidad EIA; Universidad de Antioquia through the EIA-UdeA-UdeM-project "Generacion de segundo armonico, rectificacion Optica y dispersion Raman entre estados electronicos en pozos cuanticos acoplados", CAD is grateful to the Colombian Agencies CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and project "Efectos de capas delta dopadas en pozos cuanticos como fotodetectores en el infrarrojo") and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD exclusive dedication project 2018-2019). RLR and CAD are grateful to the Universidad EIA and Universidad de Antioquia for its financial support through the EIA-UdeA-UdeM-project "Generacion de segundo armonico, rectificacion Optica y dispersion Raman entre estados electronicos en pozos cuanticos acoplados".

Published
2019

42. Optical Absorption and Electroabsorption Related to Electronic and Single Dopant Transitions in Holey Elliptical GaAs Quantum Dots

Author

R.L. Restrepo, C.A. Duque, M.E. Mora-Ramos, Alvaro Morales, Mauricio Alejandro Londoño, Esin Kasapoglu, A. Radu, El Mustapha Feddi, J.A. Vinasco, [Alejandro Vinasco, Juan -- Luis Morales, Alvaro -- Alberto Duque, Carlos] Univ Antioquia, Fac Ciencias Exactas & Nat, Inst Fis, Grp Mat Condensada, Calle 70 52-21, Medellin, Colombia -- [Alejandro Londono, Mauricio] Univ Antioquia, Fac Ciencias Exactas & Nat, Inst Matemat, Calle 70 52-21, Medellin, Colombia -- [Leon Restrepo, Ricardo] Univ EIA, Envigado 055428, Colombia -- [Eduardo Mora-Ramos, Miguel] Univ Autonoma Estado Morelos, Ctr Invest Ciencias IICBA, Ave Univ 1001, Cuernavaca 62210, Morelos, Mexico -- [Feddi, El Mustapha] Mohammed V Univ Rabat, ENSET, Grp Optoelect Semicond & Nanomat, Rabat, Morocco -- [Radu, Adrian] Univ Politehn Bucuresti, Dept Phys, 313 Splaiul Independentei, RO-060042 Bucharest, Romania -- [Kasapoglu, Esin] Cumhuriyet Univ, Dept Phys, Fac Sci, TR-58140 Sivas, Turkey, Restrepo, R. L. -- 0000-0002-0359-353X, and Feddi, El mustapha -- 0000-0001-6641-3623

Subjects
Materials science, Dopant, business.industry, donor impurity, ellipsoidal quantum dot, finite element method, GaAs, Binding energy, 02 engineering and technology, binding energy, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, Quantum dot, 0103 physical sciences, Optoelectronics, 010306 general physics, 0210 nano-technology, Absorption (electromagnetic radiation), business
Abstract

12th International Conference on Optics of Surfaces and Interfaces (OSI) -- JUN 25-30, 2017 -- Trin Coll Dublin, Sch Phys, Dublin, IRELAND, WOS: 000430113000017, The electron states in a holey elliptically shaped GaAs quantum dot are investigated within the effective mass scheme with the use of the adiabatic approximation and the finite element method. The effects of a donor impurity center and an applied electric field are particularly taken into account. Electron-impurity energies are reported as functions of both the geometry of the quantum dot and the applied field intensity, whereas temperature effects are also included. The analysis of electron-impurity intersubband transitions allows the investigation of the light absorption response of the system., CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia); CODI-Universidad de Antioquia (research project "Manipulacion de propiedades optoelectronicas de nanoestructuras semiconductoras por ondas acusticas superficiales"); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia; Universidad EIA; Universidad de Antioquia through the EIA-UdeA-UdeM-project "Desarrollo de fotodetectores en el infrarrojo usando pozos cuanticos ajustables con dopamiento delta dentro del pozo"; Colombian Oil Company ECOPETROL; Colombian Oil Company COLCIENCIAS [0266-2013], This research was partially supported by Colombian Agencies: CODI-Universidad de Antioquia (Estrategia de Sostenibilidad de la Universidad de Antioquia and research project "Manipulacion de propiedades optoelectronicas de nanoestructuras semiconductoras por ondas acusticas superficiales") and Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD and ALM exclusive dedication projects 2017-2018). RLR and CAD are grateful to Universidad EIA and Universidad de Antioquia for financial support through the EIA-UdeA-UdeM-project "Desarrollo de fotodetectores en el infrarrojo usando pozos cuanticos ajustables con dopamiento delta dentro del pozo." This work is supported by Colombian Oil Company ECOPETROL and COLCIENCIAS as a part of the research project grant No. 0266-2013.

Published
2017
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43. [Thoracic insufficiency syndrome].

Author

Ramírez N, Devaris A, Arroyo S, Restrepo RL, Cuneo A, Fernández CA, and Marrero-Ortiz P

Subjects
Adolescent, Child, Humans, Prostheses and Implants, Ribs, Titanium, Treatment Outcome, Respiratory Insufficiency, Scoliosis
Abstract

The compendium of disorders that affect the normal growth or function of the thorax will cause Thoracic Insufficiency Syndrome (TIS). TIS is defined as the inability of the chest to sustain normal breathing and/or lung growth. The etiology of the syndrome may be secondary to spinal deformities, global deformities of the chest, neuromuscular dysfunction or the combination of any these. Its manifestation is based on a history that highlights respiratory symptoms, a physical examination that demonstrates chest deformity, abnormal radiographic findings and/or computed tomography of the chest, accompanied by alterations in lung function or other studies of respiratory function. This syndrome must be treated with haste since it progressively worsens with the aggravation of the underlying condition(s) which is unfavorable to the irreversible physiological changes of the lung that occur during development, and are directly related to the respiratory insufficiencies. The vertical expandable prosthetic titanium rib (VEPTR) was developed as a treatment procedure that aims to restore the volume and function of the thorax with the purpose of enabling thoracic growth during the development of the child or adolescent. The treatment targets the components of the rib cage as a unit, in order to prevent or treat respiratory insufficiencies. Its indications include children with early development scoliosis who are prone to develop SIT. The proposed procedure entails a high incidence of complications and conflicting results that limit its efficacy as a treatment, which is why it is a subject of great controversy in the medical literature.

Published
2020

44. Donor impurity energy and optical absorption in spherical sector quantum dots.

Author

Mora-Ramos ME, El Aouami A, Feddi E, Radu A, Restrepo RL, Vinasco JA, Morales AL, and Duque CA

Abstract

The properties of the conduction band energy states of an electron interacting with a donor impurity center in spherical sector-shaped GaAs-Al 0.3 Ga 0.7 As quantum dots are theoretically investigated. The study is performed within the framework of the effective mass approximation through the numerical solution of the 3D Schrödinger equation for the envelope function via the finite element method. The modifications undergone by the spectrum due to the changes in the conical structure geometry (radius and apical angle) as well as in the position of the donor atom are discussed. With the information regarding electron states the linear optical absorption coefficient associated with transition between confined energy levels is evaluated and its features are discussed. The comparison of results obtained within the considered model with available experimental data in GaAs truncated-whisker-like quantum dots shows very good agreement. Besides, our simulation leads to identify the lowest energy photoluminescence peak as donor-related, instead of being associated to acceptor atoms, as claimed after experimental measurement (Hiruma et al. (1995) [14]). Also, a checking of our numerical approach is performed by comparing with analytical solutions to the problem of a spherical cone-shaped GaN with infinite confinement and donor impurity located at the cone apex. Coincidence is found to be remarkable., (© 2020 The Author(s).)

Published
2020
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45. Electron Raman Scattering and Raman Gain in Pyramidal Semiconductor Quantum Dots.

Author

Monsaleve-Calderón K, Gil-Corrales A, Morales AL, Restrepo RL, Mora-Ramos ME, and Duque CA

Abstract

The Raman scattering related with conduction band states in semiconductor pyramidal quantum dots is theoretically investigated. The electron Raman differential cross section and Raman gain coefficient are calculated making use of analytically determined quantum states. The energy spectrum is obtained within the effective mass approximation. The features of the Raman differential cross section are discussed in terms of their dependence on the changes of the quantum dot geometry. The variation of the Raman gain coefficient as a function of the quantum dot size and shape is also analyzed.

Published
2017
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