Antiferromagnetic Spatial Ordering in a Quenched One-dimensional Spinor Gas

TL;DR

This study experimentally demonstrates the spontaneous emergence of antiferromagnetic order in a quenched sodium spinor Bose-Einstein condensate, revealing complex nonequilibrium spin dynamics and correlations.

Contribution

First experimental observation of antiferromagnetic spatial order formation in a quenched spinor BEC with detailed correlation analysis.

Findings

Observed spontaneous antiferromagnetic order formation.

Identified distinct dynamics of spin correlations versus populations.

Documented rich nonequilibrium behavior post-quench.

Abstract

We have experimentally observed the emergence of spontaneous antiferromagnetic spatial order in a sodium spinor Bose-Einstein condensate that was quenched through a magnetic phase transition. For negative values of the quadratic Zeeman shift, a gas initially prepared in the F = 1, mF = 0 state collapsed into a dynamically evolving superposition of all 3 spin projections, mF = 0, +/-1. The quench gave rise to rich, nonequilibrium behavior where both nematic and magnetic spin waves were generated. We characterized the spatiotemporal evolution through two particle correlations between atoms in each pair of spin states. These revealed dramatic differences between the dynamics of the spin correlations and those of the spin populations.