Interband optical absorptions in a parabolic quantum dot

The linear and nonlinear optical absorptions considering excitonic effect in a parabolic quantum dot are studied. Analytic forms of the linear and third-order nonlinear optical absorption coefficients are obtained for a symmetric parabolic quantum dot using the compact density matrix formalism. Based on this model, numerical results are presented for a typical CdS parabolic quantum dot. The calculated results show that the factors of the parabolic potential confinement and the incident optical intensity have great influence on the optical absorption coefficients. Furthermore, the optical absorption saturation intensity can be controlled by adopting a proper parabolic confinement potential.