Induced electrostatic fields on optical gain in a polar quantum dot

Abstract

Exciton binding energy, optical transition energy, emission wavelength and electrostatic built-in internal fields are studied with the various magnesium alloy compositions and the dot radii in ZnO/Zn1−xMgxO cylindrical quantum dot. The induced built-in internal electric fields are found to be around the order of MV/cm and the obtained values range from 0.41 to 1.5 MV/cm. The obtained values of internal fields are used to find the optical gain and it is found to be larger than GaN materials. The effects of adding Mg composition, the built-in internal fields and the spatial confinement have great influence on the exciton states.