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Unified description of floppy and rigid rotating Wigner molecules formed in quantum dots

Constantine Yannouleas·Uzi Landman
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Abstract

Restoration of broken circular symmetry is used to explore the characteristics of the ground states and the excitation spectra of rotating Wigner molecules (RWM's) formed in two-dimensional parabolic N-electron quantum dots. In high magnetic fields, the RWM's are floppy rotors with the energies of the magic angular momentum (L) states obeying aL + b/L^{1/2}. Under such fields the ground-state energies (referenced to the kinetic energy in the lowest Landau level) approach the electrostatic energy of N point charges in the classical equilibrium molecular configuration. At zero field and strong interelectron repulsion, the RWM's behave like quasiclassical rigid rotors whose energies vary as L^2. The particular L-dependence in high B is inherent and natural to a floppy rotating WM, and it can be used as a crucial diagnostic tool for resolving the recently posed question whether the composite-fermion or the RWM picture is appropriate for QD's.

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Constantine Yannouleas, Uzi Landman. 2003-11-20. Unified description of floppy and rigid rotating Wigner molecules formed in quantum dots. https://doi.org/10.1103/physrevb.69.113306

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