Enhancement of the optical absorption in MgZnO/ZnO quantum well under external electric field

Optical absorption of electron inter-band transitions in asymmetric Mg x Zn1−x O/ZnO/Mg y Zn1−y O quantum wells with mixed phases

“…The band bowing parameter from single WZ phase by linear fit is adopted approximately as b = 0.34 eV in equation (4) [28] for avoiding repeated considerations of mixed phase effect. Electron relaxation time is taken as τ = 20 fs in equation (15) [20].…”

“…However, the mechanism for the formation of multicolor PDs in mixed phases still needs to be investigated in theory. Meanwhile, as a crucial factor of PDs, optical absorption coefficients of electron transitions in related heterostructures have been already clarified [20]. Unfortunately, as a major contribution to the electron distribution drastically affecting the absorption peaks, the built-in electric fields (BEFs) under the influence of mixed phases were neglected in the above works.…”

Resonant Tunnelling and Intersubband Optical Properties of ZnO/ZnMgO Semiconductor Heterostructures: Impact of Doping and Layer Structure Variation

“…Furthermore, linear and nonlinear optical properties in quantum heterostructures, like SLs and quantum wells based on wide-bandgap oxide semiconductors, are the focus of research due to their potential applications in optoelectronics, such as QCLs [1,[27][28][29] and RTDs [30]. The properties of these devices are based on two quantum phenomena: electronic confinement and tunnelling.…”

“…The 260 K record performance has been established due to a paradigm shift in designing structures beyond LO-phonon resonance energy [34,35], however, the fundamental limit lies in nonradiative electron-LO-phonon scattering between the lasing levels [35], and this can only be mitigated by using material systems with larger resonant LO-phonon energy. Promising alternative semiconductors to solve this problem include new material systems like zinc oxides (ZnO) with their larger LO-phonon energy (~72 meV) [27]. ZnO with a hexagonal wurtzite structure is currently emerging as a promising II-VI direct wide-bandgap semiconductor for its use in photonic devices, such as LEDs, solar cells, thin film transistors and other heterostructures [36][37][38][39].…”

Theoretical study of electronic and optical properties in doped quantum structures with Razavy confining potential: effects of external fields

“…Here, λ represents the energy and x is a column wave vector describing the electron wave function. After computing the energy levels and their corresponding wave functions, the linear, third-order nonlinear, and total optical absorption coefficients for the intersubband transitions between initial and final states E i → E f can be evaluated from [65][66][67]:…”