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    Anomalous polarization in an electric field and self-polarization in GaAs/AlAs quantum wells and quantum well wires
    (Elsevier Science Bv, 2004) Okan, SE; Erdogan, I; Akbas, H
    The response of an electron to an electric field in the infinite quantum wells and the infinite quantum well wires is investigated. Also the self-polarization effect, which can be defined as the influence of the well potential on the impurity electron, is studied for the same structures. The anomalous polarization in the excited states is found to be always exist in the presence of an electric field. Also it is shown that the external electric field polarization is intensified or weakened by an impurity ion depending on its position in the structure. (C) 2003 Elsevier B.V. All rights reserved.
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    Combined effects of the hydrostatic pressure and temperature on the self-polarization in a finite quantum well under laser field
    (Academic Press Ltd- Elsevier Science Ltd, 2021) Cicek, E.; Mese, A., I; Ozkapi, B.; Erdogan, I
    In this study, the self-polarization and binding energy of the donor impurity atom in the laser field applied Ga1_xAlxAs/GaAs quantum well are investigated under the combined influence of hydrostatic pressure and temperature. Variation of self-polarization and binding energy depending on temperature, hydrostatic pressure, impurity position, well width and laser field parameters are shown. Using the effective mass approximation, subband energy has been found by finite difference method and impurity energy has been found by variation method. Our results showed that hydrostatic pressure and temperature have a noticeable effect on the calculated selfpolarization and binding energy in a quantum well under the effect of the laser field. We think that the results obtained will be useful in determining the physical properties of the quantum well under the influence of laser field, hydrostatic pressure and temperature.
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    Donor binding energies in GaAs quantum wells considering the band nonparabolicity effects and the wavefunction elongation
    (Academic Press Ltd, 2000) Aktas, S; Okan, SE; Erdogan, I; Akbas, H; Tomak, M
    The donor binding energies in finite GaAs/GaxAl1-As-x quantum wells have been calculated by considering the confinement of electrons, which increases as the well width increases. The variational solutions have been improved by using a two-parameter trial wavefunction, and by including the conduction band nonparabolicity. It is shown that the method used gives results in agreement with those obtained in the experiments on the effective mass and the donor binding energy, both of which are strongly dependent on the well width. (C) 2000 Academic Press.
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    Electric and magnetic field effects on the self-polarization in GaAs/AlAs cylindrical quantum well-wires
    (Elsevier Science Bv, 2006) Erdogan, I; Akankan, O; Akbas, H
    In this work we have calculated the effect of the infinite cylindrical quantum well-wire barrier on the donor electron within a variational scheme. The binding energy and the self-polarization effect are calculated for different location of impurity ion as function of both electric and magnetic fields. We find that, self-polarization effect depends strongly on the applied magnetic field. (c) 2006 Published by Elsevier B.V.
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    Laser field effect on self-polarization of a donor impurity in a finite Ga1?xAlxAs/GaAs quantum well
    (Elsevier, 2021) Erdogan, I; Yavuz, S.
    The self-polarization and donor binding energy are calculated for a square Ga1?xAlxAs/GaAs quantum well under an laser field. The donor binding energy and self-polarization are obtained as a function of the laser field parameter, donor impurity position and quantum well-width. The calculations are made by means of variational and finite differences methods using the effective-mass approximation. Our results show that the laser field has remarkable effect on the self-polarization and donor binding energy. These results can be useful for studies on the electronic and optical properties of a quantum well under the influence of a laser field.
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    Self polarization in GaAs-(Ga, Al)As quantum well wires: electric field and geometrical effects
    (Elsevier Science Bv, 2005) Ulas, M; Erdogan, I; Cicek, E; Dalgic, SS
    The response of an electron to an external electric field in different shapes of infinite quantum well wires has been investigated. The self-polarization effect which can be defined as the influence of the barrier potential on the impurity electron is studied for the quantum well wire of square, rectangular and cylindrical cross-sections. An external electric field vanishes due to the self-polarization effect has been calculated. It is shown that the self-polarization effect outside of the center depends on both the geometrical form of the wire and the impurity position in the same structure. (C) 2004 Elsevier B.V. All rights reserved.
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    Self-polarization of a donor impurity for the first excited state in an Ga1-xAlxAs/GaAs quantum well
    (Indian Assoc Cultivation Science, 2021) Sucu, S.; Minez, S.; Erdogan, I
    In this study, self-polarization (SP) for the first excited state in the finite quantum well is presented by taking into account the hydrostatic pressure and the external electric field. We calculated the SP of the first excited state by using the variational method under the effective mass approximation. These calculations were made for different values of the quantum well-width, hydrostatic pressure, external electric field and impurity positions. Our results indicate that the self-polarization of the first excited state in finite quantum well depends remarkably on the hydrostatic pressure, external electric field strength and impurity position.