Effect of electric field and dot radius on the quantum state energies of an electron confined in a GaAs/GaxAl1−xAs core shell quantum dot

Abstract

In this paper the quantum state energies of an electron confined in a GaAs/GaxAl1−xAs core shell quantum dot were calculated using W.K.B approximation method, in the frame work of the effective mass approximation under external electric field. The study reveals that the electron energies of 1s and 2p states decreases with increase in applied external electric field at a given dot radius. Furthermore the electron energies of the states are found to decrease with increase in dot radius and become appreciably small <30eV with electric field of strength 5KV/cm. In addition our results show the effect of shell radius on the electronic structure. For a shell radius R1>5nm, the ground and first excited state electron energies are negligibly small and approaches to a constant value. We also display the effect of Al concentration on the electron energy levels. The electron energy increases and shows non linear dependence with the increase in Al concentration. The observed results are in agreement with the theoretical results reported in the previous literature.