Non-polar ZnCdO/ZnO step-barrier quantum wells designed for THz emission

Symmetric and asymmetric quantum wells of ZnCdO structures grown on ZnO in non-polar orientations are investigated for their potential in THz emission due to the intersubband transitions between the subbands in the conduction band. The Schro?dinger and Poisson equations are solved self-consistently for the square and step barrier quantum wells of the Zn1-xCdxO layers for x up to 0.25. The results are represented as functions of the Cd concentration in the well and step-barrier layers and their dimensions. The role of the many-body effects on the intersubband transitions is discussed. It is found that emission wavelengths between 4.5 and 8.55 THz in the step-barrier quantum wells are possible in the case of an optical pumping at a wavelength in the range of 8.27-15.7 mu m. The depolarization and excitonic shifts are found to contribute to the bare intersubband transition energies as much as their 15% at maximum.

Automated summary

Symmetric and asymmetric quantum wells of ZnCdO structures grown on ZnO in non-polar orientations were investigated for their potential in THz emission. Self-consistent solutions of the Schro?dinger and Poisson equations were used to study the effects of Cd concentration on the structures, with possible emission wavelengths between 4.5 and 8.55 THz in step-barrier quantum wells. The importance of many-body effects on intersubband transitions was also discussed.