Theoretical analysis of electron-hole alignment in InAs-GaAs quantum dots

摘要: We present a theoretical analysis of the mean electron and hole positions in self-assembled InAs-GaAs quantum-dot structures. Because asymmetric dot shape, center mass should be displaced with respect to such dots, giving rise built-in dipole moment. Theoretical calculations on ideal pyramidal dots predict localized above hole, contrary results recent Stark-effect spectroscopy. use an efficient plane-wave envelope-function technique determine ground-state electronic structure range models. In this technique, Hamiltonian matrix elements due all components potential are determined using simple analytical expressions. demonstrate that experimental data consistent truncated shape graded composition profile, indium aggregation at top surface dot.