A detailed investigation of the electronic properties of a multi-layer spherical quantum dot with a parabolic confinement

► The change in the size of well, barrier and core layers makes possible to control electronic structure of a quantum dot structure. ► The presence of an impurity in the center of the quantum dot has a great influence on the transitions between the electronic states. ► The impurity binding energies are strongly related to the widths of the well, barrier and core layers.