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Dynamical phase diagram of a one dimensional Bose gas in a box with a tunable weak-link: from Bose-Josephson oscillations to shock waves

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 نشر من قبل Romain Dubessy
 تاريخ النشر 2021
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Abhik Kumar Saha




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We study the dynamics of one-dimensional bosons trapped in a box potential, in the presence of a barrier creating a tunable weak-link, thus realizing a one dimensional Bose Josephson junction. By varying the initial population imbalance and the barrier height we evidence different dynamical regimes. In particular we show that at large barriers a two mode model captures accurately the dynamics, while for low barriers the dynamics involves dispersive shock waves and solitons. We study a quench protocol that can be readily implemented in experiments and show that self-trapping resonances can occur. This phenomenon can be understood qualitatively within the two-mode model.



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