k.P energy-band structure of ZnO/Zn1−xMgxO quantum well heterostructures

We present a k.P theoretical study of the energy band properties of würtzite ZnO/Zn1−xMgxO Quantum Well Heterostructures (QWH) as a function of the alloy composition xx in the range x<0.4x<0.4, and for various well widths. For this purpose, we use a Luttinger-type effective mass model, the 6×6 Rashba–Sheka–Pikus model, to describe the valence bands of these QWH. By using the k.P parameters available in the literature, we have first computed the energy band-structure dispersion of bulk ZnO and we have found good agreement with previous k.P, as well as, ASA-LMPTO results. Then we have computed the valence band dispersion and confinement energies in the range of interest x<0.40x<0.40 and for various well widths LZLZ. Good agreement is found with the available pump–probe PL results, for the peak energies of linear absorption for various QWH are closely fitted by using a band-offset ΔEC/ΔEV=9/1.