Coulomb repulsive correlation in systems with radial confinement: Quantum dots and the Overhauser model in an external magnetic field

Abstract

The ground-state correlation energy of an electron-negative ion system in a spherical quantum dot (QD) with parabolic confinement in an external homogeneous magnetic field is investigated. Both cases of finite and infinite potential barrier on the QD surface are considered. The theoretical analysis is carried out using a variational approach. The ground state energy of a two-electron system in a QD with harmonic-oscillator potential in a magnetic field is also determined as a function of the strength of the magnetic field and parabolic confinement. The influence of the finite potential barrier on the correlation energy of the two-electron system is also discussed. A first investigation of electron-electron correlation in a two-dimensional (2D) system with the screened Coulomb potential proposed by Overhauser but in the presence of a perpendicular magnetic field is shown to be another important application of the proposed variational wave functions.