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Classical field techniques for condensates in one-dimensional rings at finite temperatures

A. Nunnenkamp·J. N. Milstein·K. Burnett
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Abstract

For a condensate in a one-dimensional ring geometry, we compare the thermodynamic properties of three conceptually different classical field techniques: stochastic dynamics, microcanonical molecular dynamics, and the classical field method. Starting from non-equilibrium initial conditions, all three methods approach steady states whose distribution and correlation functions are in excellent agreement with an exact evaluation of the partition function in the high-temperature limit. Our study helps to establish these various classical field techniques as powerful non-perturbative tools for systems at finite temperatures.

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A. Nunnenkamp, J. N. Milstein, K. Burnett. 2007-01-12. Classical field techniques for condensates in one-dimensional rings at finite temperatures. https://doi.org/10.1103/physreva.75.033604

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