The effect of dielectric constant on binding energy and impurity self-polarization in a GaAs–Ga1−x Al x As spherical quantum dot

Abstract

The ground state, 1s, and the excited state, 2p, energies of a hydrogenic impurity in a GaAs–Ga1−x Al x As spherical quantum dot, are computed as a function of the donor positions. We study how the impurity self-polarization depends on the location of the impurity and the dielectric constant. The excited state anomalous impurity self-polarization in the quantum dot is found to be present in the absence of any external influence and strongly depends on the impurity position and the radius of the dot. Therefore, the excited state anomalous impurity self-polarization can give information about the impurity position in the system. Also, the variation of $$ E_{b1s} \,and\,E_{b2p} $$ with the dielectric constant can be utilized as a tool for finding out the correct dielectric constant of the dot material by measuring the 1s or 2p state binding energy for a fixed dot radius and a fixed impurity position.