# Emergence and scaling of spin turbulence in quenched antiferromagnetic spinor Bose-Einstein condensates

## TL;DR

This paper studies how spin turbulence and half-quantum vortices emerge and evolve in a quenched antiferromagnetic spinor Bose-Einstein condensate, revealing scaling laws and energy cascade behaviors.

## Contribution

It provides new insights into the dynamics of phase transition and turbulence formation in spinor condensates, highlighting the scaling laws and vortex behavior near the critical point.

## Key findings

- Spin turbulence emerges and decays after quenching.
- Characteristic scales scale as |q|^{-1/2}.
- Number of HQVs increases with |q| and saturates.

## Abstract

We investigate the phase transition dynamics of a quasi-2D antiferromagnetic spin-1 Bose-Einstein condensate from the easy-axis polar phase to the easy-plane polar phase, which is initiated by suddenly changing the sign of the quadratic Zeeman energy $q$. We observe the emergence and decay of spin turbulence and the formation of half-quantum vortices (HQVs) in the quenched condensate. The characteristic time and length scales of the turbulence generation dynamics are proportional to $|q|^{-1/2}$ as inherited from the dynamic instability of the initial state. In the evolution of the spin turbulence, spin wave excitations develop from large to small length scales, suggesting a direct energy cascade, and the spin population for the axial polar domains exhibit a nonexponential decay. The final equilibrated condensate contains HQVs, and the number is found to increase and saturate with increasing $|q|$. Our results demonstrate the time-space scaling properties of the phase transition dynamics near the critical point and the peculiarities of the spin turbulence state of the antiferromagnetic spinor condensate.