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Self-consistent quantum kinetics of condensate and non-condensate via a coupled equation of motion formalism

N. P. Proukakis
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Abstract

This paper extends an earlier quantum kinetics treatment for dilute, weakly-interacting, partially Bose-Einstein condensed gases, presented by the author elsewhere [J. Res. Natl. Inst. Stand. Technol. 101, 457 (1996)], by consistently treating the dynamics of the uncondensed atoms to the same level of approximation as the condensed atoms. Our method is based on a hierarchy of coupled equations of motion for the condensate mean field and fluctuations around this mean field, truncated to second order in the (effective two-body) interatomic potential, and with suitable decoupling approximations for higher order correlations. By applying perturbation theory in the Hartree-Fock-Bogoliubov basis, we re-derive the quantum kinetic theory of Walser et al. [Phys. Rev. A 59, 3878 (1999)], which further indicates the consistency of our treatment to the Kadanoff-Baym non-equilibrium Green's functions formalism for trapped gases.

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N. P. Proukakis. 2002-03-21. Self-consistent quantum kinetics of condensate and non-condensate via a coupled equation of motion formalism. https://doi.org/10.1088/0953-4075%2F34%2F23%2F317

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