Group velocity of light in a three level ladder-type spherical quantum dot with hydrogenic impurity

In this paper we analyzed the group velocity of light and slow light in the spherical quantum dot with on-center hydrogenic impurity. To do this, we considered a ladder like system which consist of three energy levels of hydrogen impurity 1s0, 2p−1, and 3d−2, together with the probe and control laser fields, which induce σ− transitions. The Scrödinger equation is solved in order to obtain eigenfunctions, eigenvalues and dipole transition moments. Optical Bloch equations are than solved in a stationary regime, and the group velocity of probe laser field examined in detail. Dependence of the group velocity of light is discussed as a function of the spherical quantum dot radius, probe field frequency, control laser field intensity and control laser field detuning.