  The electronic properties of semiconductor, vertical, double quantum dot
systems with few electrons are investigated by means of analytic,
configuration-interaction, and mean-field methods. The combined effect of a
high magnetic field, electrostatic confinement, and inter-dot coupling, induces
a new class of few-electron ground states absent in single quantum dots. In
particular, the role played by the isospin (or quantum dot index) in
determining the appearance of new ground states is analyzed and compared with
the role played by the standard spin.
