Few-electron systems in quantum cylinders

Abstract

Systems of excess electrons confined in cylindrical semiconductor quantum dots, i.e., artificial atoms of cylindrical symmetry, are studied by the unrestricted Hartree-Fock method. The confinement potential is assumed in the form of three-dimensional cylindrically symmetric potential well of finite depth. The calculations have been performed for artificial atoms with the number of electrons from 1 to 10. We have taken into account the external magnetic field applied parallel to the axis of the cylinder and studied the influence of quantum-dot geometry on the maximum number of confined electrons and the ground-state spinorbital configuration. The applicability of the quasi-two-dimensional model of quantum dots has been discussed and the magnetic-field behavior has been predicted for quantum cylinders of comparable diameter and height. We have applied the present model to a description of single-electron charging of self-assembled quantum dots and obtained a good agreement with capacitance-spectroscopy data.