Composite-fermion description of correlated electrons in quantum dots: Low-Zeeman-energy limit

Spectral properties of rotating electrons in quantum dots and their relation to quantum Hall liquids

The exact diagonalization technique is used to study many-particle properties of interacting electrons with spin, confined in a two-dimensional harmonic potential. The single-particle basis is limited to the lowest Landau level. The results are analysed as a function of the total angular momentum of the system. Only at angular momenta corresponding to the filling factors 1, 1/3, 1/5, etc is the system fully polarized. The lowest energy states exhibit spin waves, domains, and localization, depending on the angular momentum. Vortices exist only at excited polarized states. The high angular momentum limit shows localization of electrons and separation of the charge and spin excitations.

A quasiclassical approach to strongly correlated quantum dots in intense magnetic fields

We present a general quasiclassical description of parabolic many-electron quantum dots in the limit of high magnetic fields. The key points of our approach are the transition to a rotating frame of reference, in order to decouple rotational and vibrational modes, as well as the recognition and inclusion of the role of potential anisotropy felt by the vibrational modes. We are able to obtain the complete wavefunction of quantum dots containing any number of electrons in the Gaussian form, and present results concerning inter-particle correlation and deformation of large quantum dots.

Even-odd effect in spontaneously coherent bilayer quantum Hall droplets

Using exact diagonalization in the disk geometry we predict a novel even-odd effect in the Coulomb-blockade spectra of vertically coupled double quantum dots under an external magnetic field. The even-odd effect in the tunneling conductance is a direct manifestation of spontaneous interlayer phase coherence, and is similar to the even-odd resonance in the Cooper pair box problem in mesoscopic superconducting grains. Coherent fluctuations in the number of Cooper pairs in superconductors are analogous to the fluctuations in the relative number difference between the two layers in quantum Hall droplets.