Multiple-scale approach for the expansion scaling of superfluid quantum gases

TL;DR

This paper introduces a multiple-scale method to derive perturbative solutions for the expansion dynamics of superfluid ultracold gases, improving accuracy over previous models by addressing secular terms and calculating next-to-leading corrections.

Contribution

It presents a novel multiple-scale approach to solve expansion scaling equations, enhancing the precision of aspect ratio predictions for superfluid quantum gases.

Findings

Improved asymptotic aspect ratio calculations.

Effective treatment of secular terms in perturbation theory.

Enhanced accuracy over previous models.

Abstract

We present a general method, based on a multiple-scale approach, for deriving the perturbative solutions of the scaling equations governing the expansion of superfluid ultracold quantum gases released from elongated harmonic traps. We discuss how to treat the secular terms appearing in the usual naive expansion in the trap asymmetry parameter epsilon, and calculate the next-to-leading correction for the asymptotic aspect ratio, with significant improvement over the previous proposals.