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Localization of weakly interacting Bose gas in quasiperiodic potential

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 نشر من قبل Sayak Ray
 تاريخ النشر 2015
  مجال البحث فيزياء
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We study the localization properties of weakly interacting Bose gas in a quasiperiodic potential commonly known as Aubry-Andre model. Effect of interaction on localization is investigated by computing the `superfluid fraction and `inverse participation ratio. For interacting Bosons the inverse participation ratio increases very slowly after the localization transition due to `multisite localization of the wave function. We also study the localization in Aubry-Andre model using an alternative approach of classical dynamical map, where the localization is manifested by chaotic classical dynamics. For weakly interacting Bose gas, Bogoliubov quasiparticle spectrum and condensate fraction are calculated in order to study the loss of coherence with increasing disorder strength. Finally we discuss the effect of trapping potential on localization of matter wave.

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