Phase Winding a Two-Component BEC in an Elongated Trap: Experimental Observation of Moving Magnetic Orders and Dark-bright Solitons

TL;DR

This paper experimentally explores phase winding dynamics in a two-component Bose-Einstein condensate, revealing stable magnetic orders and enabling the generation of dark-bright solitons through controlled phase winding.

Contribution

It demonstrates the creation of moving magnetic orders and dark-bright solitons in a two-component BEC using phase winding, highlighting new nonlinear phenomena.

Findings

Observation of stable moving magnetic order under magnetic field gradient

Generation of numerous dark-bright solitons via phase winding

Mapping of dynamics to a two-component Bose-Hubbard model

Abstract

We experimentally investigate the phase winding dynamics of a harmonically trapped two-component BEC subject to microwave induced Rabi oscillations between two pseudospin components. While the single particle dynamics can be explained by mapping the system to a two-component Bose-Hubbard model, nonlinearities due to the interatomic repulsion lead to new effects observed in the experiments: In the presence of a linear magnetic field gradient, a qualitatively stable moving magnetic order that is similar to antiferromagnetic order is observed after critical winding is achieved. We also demonstrate how the phase winding can be used as a new tool to generate copious dark-bright solitons in a two-component BEC, opening the door for new experimental studies of these nonlinear features.