Holes Behavior in the Valence Band of a Quantum Well Heterostructure〖Zn〗_(1-x) 〖Mg〗_x O/ZnO/ 〖Zn〗_(1-x) 〖Mg〗_x O

Abstract

This paper is a study of quantum well heterostructure made up by a zinc oxide (ZnO) thin layer (well) sandwiched between two Zn_1-xMg_xO layers acting as barriers potential. Setting the width of the well to a = 10 nm, the allowed quantum states in the structure and the wave function profile are examined for different values of the parameter x : x = 0.1, x = 0.2.... A previous paper was devoted to the conduction band (CB), this one concerns quantum states in the valence band (VB). The comparison between the results shows that holes in the valence band approximately have similar behaviour than electrons in the conduction band.  The calculated wavelengths corresponding to intra-band transitions are in the infrared domain of the electromagnetic spectrum. These wavelengths depend on the parameter x, allowing to control the optoelectronic properties of the quantum well by adjusting the concentration x during the growth process. Therefore, for the same value of x, the quantum states number in the valence band are more important than those in the conduction band. This result can be explained by the split noticed in the valence band.