Electronic and optical properties of ZnO quantum well structures

This study investigates optical properties as a function of internal and external fields in the quantum well (QW). Optical properties of CdZnO/MgZnO QW structures, considering various applied electric fields are evaluated by using many-body effects. The strain-induced piezoelectric polarization and the spontaneous polarization can be reduced effectively by applied electric field in CdZnO/ZnMgO quantum well (QW) structures with high Cd composition. That is, optical properties as a function of internal and external fields in the CdZnO/ZnMgO QW with various applied electric field result in the increased optical gain due to the fact that the QW potential profile is flattened as a result of the compensation of the internal field by the reverse field as confirmed by Stark shifts. These results demonstrate that a high-performance optical device operation can be realized in CdZnO/MgZnO QW structures by reducing the droop phenomenon.