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Universal aspects of a strongly interacting impurity in a dilute Bose condensate

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 نشر من قبل Pietro Massignan
 تاريخ النشر 2020
  مجال البحث فيزياء
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We study the properties of an impurity immersed in a weakly interacting Bose gas, i.e., of a Bose polaron. In the perturbatively-tractable of limit weak impurity-boson interactions many of its properties are known to depend only on the scattering length. Here we demonstrate that for strong (unitary) impurity-boson interactions all static quasiproperties of a Bose polaron in a dilute Bose gas, such as its energy, its residue, its Tans contact and the number of bosons trapped nearby the impurity, depend on the impurity-boson potential via a single parameter.



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