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arXiv · 1203.4162

Negative Temperature States in the Discrete Nonlinear Schroedinger Equation

S. Iubini·R. Franzosi·R. Livi·G. -L. Oppo·A. Politi
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Abstract

We explore the statistical behavior of the discrete nonlinear Schroedinger equation. We find a parameter region where the system evolves towards a state characterized by a finite density of breathers and a negative temperature. Such a state is metastable but the convergence to equilibrium occurs on astronomical time scales and becomes increasingly slower as a result of a coarsening processes. Stationary negative-temperature states can be experimentally generated via boundary dissipation or from free expansions of wave packets initially at positive temperature equilibrium.

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S. Iubini, R. Franzosi, R. Livi, G. -L. Oppo, A. Politi. 2012-03-19. Negative Temperature States in the Discrete Nonlinear Schroedinger Equation. https://doi.org/10.1088/1367-2630%2F15%2F2%2F023032

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