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Bosons in a two-dimensional bichromatic quasiperiodic potential: Analysis of the disorder in the Bose-Hubbard parameters and phase diagrams

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 نشر من قبل Astrid Elisa Niederle
 تاريخ النشر 2015
  مجال البحث فيزياء
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Experimental realizations of disorder in optical lattices generate a distribution of the Bose-Hubbard (BH) parameters, like on-site potentials, hopping strengths, and interaction energies. We analyze this distribution for bosons in a bichromatic quasi-periodic potential by determining the generalized Wannier functions and calculating the corresponding BH parameters. Using a local mean-field cluster analysis, we study the effect of the corresponding disorder on the phase diagrams. We find a substantial amount of disorder in the hopping strengths, which produces strong deviations from the phase diagram of the disordered BH model with solely random on-site potentials.



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