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Wigner molecules in quantum dots

Boris Reusch·Wolfgang Häusler·Hermann Grabert
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Abstract

We perform unrestricted Hartree-Fock (HF) calculations for electrons in a parabolic quantum dot at zero magnetic field. The crossover from Fermi liquid to Wigner molecule behavior is studied for up to eight electrons and various spin components $S_z$. We compare the results with numerically exact path-integral Monte Carlo simulations and earlier HF studies. Even in the strongly correlated regime the symmetry breaking HF solutions provide accurate estimates for the energies and describe the one-particle densities qualitatively. However, the HF approximation favors the formation of a Wigner molecule and produces azimuthal modulations of the density for even numbers of electrons in one spatial shell.

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Boris Reusch, Wolfgang Häusler, Hermann Grabert. 2000-08-30. Wigner molecules in quantum dots. https://doi.org/10.1103/physrevb.63.113313

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