Period-doubled breathing in trapped Bose-Einstein condensates

TL;DR

This paper investigates how a trapped Bose-Einstein condensate responds to periodic driving, revealing period-doubled and chaotic behaviors near resonance, with theoretical models compared to full numerical solutions.

Contribution

It demonstrates the occurrence of period-doubled motion in a BEC under periodic modulation and compares variational and full solutions, highlighting the limitations of simplified models.

Findings

Period-doubled motion occurs near resonance with strong driving.

Chaotic oscillations are predicted by a variational model.

Full Gross-Pitaevskii solutions show agreement with experimental conditions.

Abstract

The response of a trapped Bose-Einstein condensed gas to a periodic driving force is studied theoretically in the framework of the nonlinear Gross-Pitaevskii equation. The monopole mode is driven by periodical modulation of the frequency of the isotropic harmonic trapping potential. Period-doubled motion is shown to occur when the driving is strong and close to resonance with the monopole mode. A variational model predicts chaotic oscillations but is found to disagree with the full solutions to the Gross-Pitaevskii equation.