Bound Polaron In Quantum Dot Quantum Well Structure

Within the framework of effective mass approximation, the bound polaron in quantum dot quantum well (QDQW) structure have been investigated theoretically. There are two parts in this work.Firstly, the special properties for QDQW structure are introduced. The development of the theoretical studies for the electrons, hydrogenic impurity states and electron-phonon interaction in QDQW structure is reviewed. The motivation of the present work is clarified.Secondly, within the framework of effective mass approximation, we studied the binding energy of the hydrogenic impurity in a QDQW structure by applying variational approach. The electron-phonon and ion-longitudinal-optical (LO) phonon interactions are taken into account in the calculation. We have performed numerical calculation on CdS/HgS QDQW structure embedded in an insulator matrix. The results show that the binding energy decreases with the increasing of core radius. It is also observed that the binding energy exhibits a maximum with the increasing of well-width. The LO phonon effect lowers the binding energy of the on-center impurity and decreases sharply with increasing the well-width.