External electric field effect on exciton binding energy in GaAs /GaAlAs cylindrical quantum dots with asymmetric axial potential

Abstract

Abstract The present study investigates theoretically the role of applied electric field on the exciton binding energy and photoluminescence energy in cylindrical quantum dot (QD) by considering an asymmetric axial potential. As a framework, we have considered the variational approach and the correlation between the electron and hole in the trial wave function within the effective-mass approximation. We have calculated the exciton binding energy of the ground state and the photoluminescence energy as the function of the geometry and the strength of the applied electric field along the growth direction of the cylinder. Our numerical findings for GaAs/Ga(1-x)Al(x)As have shown that the binding energy is decreasing function of the electric field strength. Also, we have found that the exciton binding energy is decreasing function of the QD height with and without electric field effect. Furthermore, the photoluminescence energy depends on the effects of electric field, the geometrical confinement and the aluminum concentrations in the barrier materials.