Figure 4.

The lowest electronic states in a ZnS/CdS/ZnS spherical core/shell/shell quantum dot as functions of the applied electric field. In (a), results are presented without, and in (b) with on-center donor impurity effects, with $R_1=4$ nm, $R_2=11$ nm, and $R_3=12$ nm. Different values of the m-quantum number and without external magnetic field effects have been considered. Labels above each of the curves give the values of the m-quantum number. The inset in (b) corresponds to the ground state (the lowest state with $m=0$) binding energy as a function of the applied electric field.