Quantum Kinetic Theory of Condensate Growth---Comparison of Experiment and Theory

TL;DR

This paper extends a quantum kinetic model of Bose-Einstein condensate growth by including detailed level occupations, achieving good experimental agreement and confirming the kinetic evolution picture up to condensate initiation.

Contribution

It introduces a comprehensive model accounting for lower and higher trap level occupations, improving the understanding of condensate growth dynamics.

Findings

Good agreement with experimental data at higher temperatures

Confirmation of the kinetic evolution region before condensate initiation

Post-initiation growth follows original equations with increased rate coefficient W^{+}

Abstract

In a major extension of our previous model (C.W. Gardiner, P. Zoller, R.J. Ballagh and M.J. Davis, Phys. Rev. Lett. 79, 1793 (1997)) of condensate growth, we take account of the evolution of the occupations of lower trap levels, and of the full Bose-Einstein formula for the occupations of higher trap levels. We find good agreement with experiment, especially at higher temperatures. We also confirm the picture of the ``kinetic'' region of evolution, introduced by Kagan et al, for the time up to the initiation of the condensate. The behavior after initiation essentially follows our original growth equation, but with a substantially increased rate coefficient W^{+}.