In this study, we have calculated the linear, nonlinear and total refractive index changes and absorption coefficients for the transitions 1s-1p, 1p-1d and 1d-1f in a spherical quantum dot with parabolic potential. Quantum Genetic Algorithm (QGA) and Hartree-Fock-Roothaan (HFR) method have been employed to calculate the wavefuctions and energy eigenvalues. The results show that impurity, dot radius, stoichiometric ratio, incident optical intensity and carrier density of the system have important effects on the optical refractive index changes and absorption coefficients. Also, we find that as the transitions between orbitals with big l value move to lower energy region in case with parabolic potential, in case without parabolic potential these transitions move to higher energy region. © 2012 Elsevier B.V. All rights reserved.