Nonlinear intersubband optical absorption of Si delta-doped GaAs under an electric field

Yildirim, Hasan
Tomak, Mehmet
We study the nonlinear intersubband optical absorption of a single Si delta-doped GaAs sheet placed in the middle of a GaAs quantum well and subjected to an electric field. The Schrodinger and Poisson equations are solved self-consistently for various electric field strengths. The self-consistent solutions provide us with the correct confining potential, the wave functions, the corresponding subband energies and the subband occupations. The nonlinear optical intersubband absorption spectra are discussed within the framework of the density matrix formulation for various electric field strengths, well widths, and sheet thicknesses in which Si atoms are distributed uniformly. We include both the depolarization and exciton shifts in calculations. The depolarization effect not only shifts the peak value but also makes the nonlinear absorption spectrum strongly asymmetric with the increasing intensity of the optical field. The blue-shift associated with the depolarization shift is decreased when the intensity is increased. The absorption line shape becomes more asymmetric at smaller well widths and thicker doping layers. The electric field, restores the symmetry of the absorption line shape at larger well widths and thinner doping layers, but it decreases the peak value of the line shape. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


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A theoretical study of the effect of the confining potential on the nonlinear optical properties of two dimensional quantum dots is performed. A three-parameter Woods-Saxon potential is used within the density matrix formalism. The control of confinement by three parameters and an applied electric field gives one quite an advantage in studying their effects on the nonlinear properties. The coefficients investigated include the optical rectification, second and third-harmonic generation and the change in the...
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In this study, a theoretical investigation of intersubband nonlinear optical rectification in Alx1Ga1-x1As/ GaAs/AlxrGa1-xrAs asymmetric rectangular quantum wells is presented. The electronic states in the asymmetric rectangular quantum well are described within the framework of the envelope function approach including the effects of band nonparabolicity and the effective mass mismatch. The nonlinear optical rectification is calculated using the density matrix formalism. It is found that the nonlinear optic...
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Sahin, M; Tomak, Mehmet (American Physical Society (APS), 2005-09-01)
We investigate the electronic structure of a many-electron spherical quantum dot with and without hydrogenic impurity. The number of electrons is taken as N=18. The density functional theory is used within local density approximation. Total energy, chemical potential, addition energy spectra, and the shell structure are determined and the results obtained are compared for cases with and without impurity. It is observed that the capacitive energy with the impurity increases in the 1s shell with respect to th...
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Citation Formats
H. Yildirim and M. Tomak, “Nonlinear intersubband optical absorption of Si delta-doped GaAs under an electric field,” PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS, pp. 2874–2881, 2006, Accessed: 00, 2020. [Online]. Available: