Binding energy of hydrogenic impurity in GaAs/Ga1-xAlxAs multi-quantum-dot structure

In this paper, we perform a theoretical study, using a variational method, of the binding energy of ground state for hydrogenic impurity in the multi-quantum-dot structure. It is found that the binding energy is not only as a function of the size of the system in the x-y plane, but also the barrier thickness and the width of a dot in the z direction. Especially, when the barrier thickness is equal to the width of a dot, there are two peaks in the behavior of the binding energy as a function of the barrier thickness. All these behaviors of the binding energy are determined by the competition between the localization effect of the wave function and the tunneling effect of the wave function due to an increase or decrease in the barrier thickness and the width of a dot. Moreover, we also investigate the behavior of binding energy with different impurity position.