Deformed molecular states of quantum dots in strong magnetic fields

The effect of a shearing electric field on molecular states of electrons in quantum dots in strong magnetic fields is investigated theoretically. The electron density in circularly symmetric dots is circularly symmetric but t he pair correlation function has peaks whose positions have the same symmet ry as the classical energy minimum. For small numbers of electrons this is analogous to a rotating ring of electrons. The shearing electric field brea ks the circular symmetry and stretches the ring, leading to states with lin ear symmetry. This transition is found to have a strong effect on the addit ion energy of a dot and can be either sudden or continuous, depending on th e value of the magnetic field. It may be possible to use this effect as an experimental probe of the physical nature of dot states. (C) 2001 Elsevier Science B.V. All rights reserved.