Coulomb crystallites from harmonically confined charged bosons in two dimensions

MEŞE A. İ., Capuzzi P., Akdeniz Z., OKAN Ş. E., Tosi M.

Journal of Physics Condensed Matter, cilt.20, sa.33, 2008 (SCI-Expanded, Scopus)

Özet

We exploit rotational-symmetry breaking in the one-body density to examine the formation of structures in systems of N strongly coupled charged bosons with logarithmic repulsions inside isotropic two-dimensional harmonic traps, with N in the range from 2 to 7. The results serve as a map for ordered arrangements of vortices in a trapped Bose-Einstein condensate. Two types of N-body wavefunctions are assumed: (i) a permanent of N identical Gaussian orbitals centred at variationally determined sites, and (ii) a permanent of N orthogonal orbitals built from harmonic-oscillator energy eigenstates. With increasing coupling strength, the bosons in the orbitals localize into polygonal-ringlike crystalline patterns ('Wigner molecules'), whereas the wavefunctions describe low energy excited states containing delocalized bosons as in supersolid crystallites ('supermolecules'). For N = 2 at strong coupling both states describe a Wigner dimer. © IOP Publishing Ltd.