Single dot and strongly coupled double dots at high magnetic fields

Circular vertical semiconductor single quantum dot artificial atoms and strongly coupled double quantum dot artificial molecules are investigated at high magnetic (B-) fields up to View the MathML source. The phase diagrams showing the evolution with B-field of the conductance peaks reflecting the electro-chemical potential of the N-electron ground states for N from zero to about 20 are compared, and the origin of the differences is discussed. In particular, the stability of the spin-polarized maximum density droplet (MDD) at filling factor, ν=1, is much reduced in the double dot system compared to the single dot system.