Eur. Phys. J. B 26, 241-252 (2002)
https://doi.org/10.1140/epjb/e20020086

Electronic properties of model quantum-dot structures in zero and finite magnetic fields

Laboratory of Physics, Helsinki University of Technology, PO Box 1100, 02015 HUT, Finland

Corresponding author: ^a hri@hugo.hut.fi

Received: 16 October 2001
Revised: 17 January 2002
Published online: 15 March 2002

Abstract

We have computed electronic structures and total energies of circularly confined two-dimensional quantum dots and their lateral dimers in zero and finite uniform external magnetic fields using different theoretical schemes: the spin-density-functional theory (SDFT), the current-and-spin-density-functional theory (CSDFT), and the variational quantum Monte Carlo (VMC) method. The SDFT and CSDFT calculations employ a recently-developed, symmetry-unrestricted real-space algorithm allowing solutions which break the spin symmetry. Results obtained for a six-electron dot in the weak confinement limit and in zero magnetic field as well as in a moderate confinement and in finite magnetic fields enable us to draw conclusions about the reliability of the more approximative SDFT and CSDFT schemes in comparison with the VMC method. The same is true for results obtained for the two-electron quantum dot dimer as a function of inter-dot distance. The structure and role of the symmetry-breaking solutions appearing in the SDFT and CSDFT calculations for the above systems are discussed.