Spin Turbulence in a Trapped Spin-1 Spinor Bose--Einstein Condensate

TL;DR

This paper investigates spin turbulence in a trapped spin-1 Bose--Einstein condensate, revealing a -7/3 power law in the energy spectrum and exploring its relation to spin vector dynamics.

Contribution

It demonstrates the emergence of a -7/3 power law in a trapped system and links it to the motion of the spin density vector, extending previous uniform system results.

Findings

The energy spectrum follows a -7/3 power law in the ferromagnetic case.

Spin turbulence is generated by instability of the initial helical structure.

The -7/3 law is connected to the dynamics of the spin density vector.

Abstract

We numerically study spin turbulence in a two-dimensional trapped spin-1 spinor Bose--Einstein condensate, focusing on the energy spectrum. The spin turbulence in the trapped system is generated by instability of the helical structure of the spin density vector in the initial state. Our numerical calculation finds that in the trapped system the spectrum of the spin-dependent interaction energy in the ferromagnetic case exhibits a -7/3 power law, which was confirmed in a uniform system by our previous study. The relation between the -7/3 power law and the motion of the spin density vector is discussed by investigating the orbits of dynamical variables in the spin space.