Engineering Dark Solitary waves in Ring-Trap Bose-Einstein condensates

TL;DR

This paper explores how to generate and observe stable counter-propagating dark solitary waves in a ring-shaped Bose-Einstein condensate, analyzing their dynamics and stability under realistic experimental conditions.

Contribution

It demonstrates the feasibility of creating and studying dark solitary waves in a ring trap BEC, identifying optimal parameters and regimes for experimental realization.

Findings

Stable solitonic motion persists after multiple collisions.

Snaking instabilities lead to decay into vortical structures.

Optimal parameters for experimental observation are identified.

Abstract

We demonstrate the feasibility of generation of quasi-stable counter-propagating solitonic structures in an atomic Bose-Einstein condensate confined in a realistic toroidal geometry, and identify optimal parameter regimes for their experimental observation. Using density engineering we numerically identify distinct regimes of motion of the emerging macroscopic excitations, including both solitonic motion along the azimuthal ring direction, such that structures remain visible after multiple collisions even in the presence of thermal fluctuations, and snaking instabilities leading to the decay of the excitations into vortical structures. Our analysis, which considers both mean field effects and fluctuations, is based on the ring trap geometry of Murray et al. Phys. Rev. A 88 053615 2013.