Binding energy of excitons in spherical quantum dot quantum well with uniform electric field

Excitons in CdS/HgS/CdS spherical quantum dot quantum well are studied theoretically in the framework of the effective mass approximation. An infinitely deep potential describes the effect of quantum confinement. The binding energy with and without applied electric field is determined by the Ritz method. The binding energy is found to strongly depend on the inner and outer radii. We have demonstrated the existence of the critical value which may be used to distinguish the three-dimensional confinement from the spherical surface confinement. The influence of a uniform electric field is analyzed. It is found that the Stark effect appears even for very small size and the energy shift is more significant when the exciton is placed at the spherical surface.