Accidental suppression of Landau damping of the transverse breathing mode in elongated Bose-Einstein condensates

TL;DR

This paper investigates the transverse breathing mode in elongated Bose-Einstein condensates, revealing an accidental suppression of Landau damping due to a collective oscillation mode involving both the condensate and thermal cloud, with results aligning well with experiments.

Contribution

It uncovers a specific collective mode that suppresses Landau damping, providing a detailed finite temperature simulation that matches experimental observations.

Findings

Existence of an in-phase collective oscillation mode

Suppression of Landau damping in this mode

Excellent agreement between simulation and experiment

Abstract

We study transverse radial oscillations of an elongated Bose-Einstein condensate using finite temperature simulations, in the context of a recent experiment at ENS. We demonstrate the existence of a mode corresponding to an in-phase collective oscillation of both the condensate and thermal cloud. Excitation of this mode accounts for the very small damping rate observed experimentally, and we find excellent quantitative agreement between experiment and theory. In contrast to other condensate modes, interatomic collisions are found to be the dominant damping mechanism in this case.