Crystalline character of high-magnetic-field cusp states in quantum dots

Conditional probability distributions from exact diagonalization are used to investigate the crystalline or liquid character of the downward cusp states in parabolic quantum dots (QD's) at high magnetic fields. These states are crystalline in character for fractional fillings covering both low and high values, unlike the liquid Jastrow-Laughlin wave functions, but in remarkable agreement with the rotating-electron-molecule ones [Phys. Rev. B 66, 115315 (2002)]. The cusp states are precursors to the bulk fractional quantum Hall states (and not to the bulk Wigner crystal), since the collective rotation stabilizes the rotating Wigner molecule (formed in the QD) relative to the static one.