Description of the Properties of Self-Assembled Quantum Dots Within the Band-Structure Model

Abstract

A method for creating self-assembled dots (SAD’s) is presented in Sect. 2.6. In this chapter we shall concentrate on self-assembled dots in the shape of spherical lenses shown in Fig. 8.1 (for the description of properties of pyramidal SAD’s see [47]). Such a dot is formed on a narrow wetting layer of thickness t _w, and modeled as a part of a sphere of height h and radius at the base _s . The conduction-band edge in the material of the wetting layer and the dot lies below that in the surrounding material [114, 115]. Thus, the electrons are confined in the narrow wetting-layer quantum well due to the step in the conduction-band edge at the interface, and they are further localized in the area of the dot due to the locally increased thickness of the layer. The effective lateral potential V(r,z) that acts on the electrons confined in the wetting layer is shown in the corner of Fig. 8.1.