Impurity effects on optical property of a spherical quantum dot in the presence of an electric field

An investigation of the optical properties of a spherical quantum dot (QD) with parabolic confinement potential containing one electron has been performed for the cases with a donor impurity and an acceptor impurity in the presence of an electric field. The oscillator strength between the ground and the first excited states in the QD has been calculated as functions of the confinement strength and the applied electric field. Based on the computed energies and wave functions, the linear, third-order nonlinear, the total optical absorption coefficients and the optical refractive index have been examined in detail. The results are presented as a function of the incident photon energy for the different values of the confinement strength and the electric field. It is found that the optical properties of a QD are strongly affected not only by the confinement strength, the applied electric field but also by the property of the impurity. (C) 2010 Elsevier B.V. All rights reserved.