Effect of conduction band non-parabolicity on bound polaron fundamental state in GaN/InN core shell quantum dots

Abstract

In this paper, we present a theoretical investigation on the polaronic, impurity position and quantum confinement effects on the ground state binding energy of single dopant confined in cubic GaN/InN core/shell quantum dots. Within the framework of the effective mass and non-parabolic approaches, the Schrödinger equation is numerically solved by using the Ritz variational method. The polaronic corrections are included via the renormalization of the effective mass and a phonon-modified electron-impurity Coulombic interaction. It is found that the influence of both electron-phonon interaction and the band non-parabolicity result in the reduction of the ground state binding energy. The inclusion of the non-parabolicity leads to stronger decrease of the magnitude of the impurity binding energy. This points at the importance of including such element for an appropriate quantitative description of the spectrum of coupled electron-donor-impurity systems in nitride core/shell quantum dots.