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Condensation transition and ensemble inequivalence in the Discrete Nonlinear Schrodinger Equation

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 نشر من قبل Giacomo Gradenigo
 تاريخ النشر 2021
  مجال البحث فيزياء
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The thermodynamics of the discrete nonlinear Schrodinger equation in the vicinity of infinite temperature is explicitly solved in the microcanonical ensemble by means of large-deviation techniques. A first-order phase transition between a thermalized phase and a condensed (localized) one occurs at the infinite-temperature line. Inequivalence between statistical ensembles characterizes the condensed phase, where the grand-canonical representation does not apply. The control over finite size corrections of the microcanonical partition function allows to design an experimental test of delocalized negative-temperature states in lattices of cold atoms.



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