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arXiv · 2106.03698

Condensation transition and ensemble inequivalence in the Discrete Nonlinear Schr\"odinger Equation

Giacomo Gradenigo·Stefano Iubini·Roberto Livi·Satya N. Majumdar
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Abstract

The thermodynamics of the discrete nonlinear Schr\"odinger 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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Giacomo Gradenigo, Stefano Iubini, Roberto Livi, Satya N. Majumdar. 2021-06-07. Condensation transition and ensemble inequivalence in the Discrete Nonlinear Schr\"odinger Equation. https://doi.org/10.1140/epje%2Fs10189-021-00046-5

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