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arXiv · 1206.0145

A Dynamical Self-Consistent Finite Temperature Kinetic Theory: The ZNG Scheme

A. J. Allen·C. F. Barenghi·N. P. Proukakis·E. Zaremba
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Abstract

We review a self-consistent scheme for modelling trapped weakly-interacting quantum gases at temperatures where the condensate coexists with a significant thermal cloud. This method has been applied to atomic gases by Zaremba, Nikuni, and Griffin, and is often referred to as ZNG. It describes both mean-field-dominated and hydrodynamic regimes, except at very low temperatures or in the regime of large fluctuations. Condensate dynamics are described by a dissipative Gross-Pitaevskii equation (or the corresponding quantum hydrodynamic equation with a source term), while the non-condensate evolution is represented by a quantum Boltzmann equation, which additionally includes collisional processes which transfer atoms between these two subsystems. In the mean-field-dominated regime collisions are treated perturbatively and the full distribution function is needed to describe the thermal cloud, while in the hydrodynamic regime the system is parametrised in terms of a set of local variables. Applications to finite temperature induced damping of collective modes and vortices in the mean-field-dominated regime are presented.

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A. J. Allen, C. F. Barenghi, N. P. Proukakis, E. Zaremba. 2012-06-01. A Dynamical Self-Consistent Finite Temperature Kinetic Theory: The ZNG Scheme. https://doi.org/10.1142/9781848168121_0005

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