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

Allen, AJ; Barenghi, CF; Proukakis, NP; Zaremba, E

doi:10.1142/9781848168121_0005

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

Lookup NU author(s): Dr Joy Allen ORCiD, Professor Carlo Barenghi, Professor Nikolaos Proukakis ORCiD

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

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.