Random spin textures in turbulent spinor Bose-Einstein condensates

TL;DR

This paper numerically studies stationary turbulent states in spin-1 Bose-Einstein condensates, revealing isotropic spin textures, a -7/3 energy spectrum, and statistical properties akin to Haar randomness, with implications for experimental tests.

Contribution

It introduces a detailed numerical analysis of turbulence in spinor BECs, including spin texture characterization and statistical ensemble comparisons, advancing understanding of nonequilibrium quantum turbulence.

Findings

Isotropic spin textures confirmed in turbulent states.

Observed -7/3 power-law in energy spectrum.

Spin state ensemble resembles Haar random ensemble.

Abstract

We numerically investigate the stationary turbulent states of spin-1 Bose-Einstein condensates under continuous spin driving. We analyze the entanglement entropy and magnetization correlation function to demonstrate the isotropic nature of the intricate spin texture that is generated in the nonequilibrium steady state. We observe a $-7/3$ power-law behavior in the spin-dependent interaction energy spectrum. To gain further insight into the statistical properties of the spin texture, we introduce a spin state ensemble obtained through position projection, revealing its close resemblance to the Haar random ensemble for spin-1 systems. We also present the probability distribution of the spin vector magnitude in the turbulent condensate, which can be tested in experiments. Our numerical study highlights the characteristics of stationary turbulence in the spinor BEC system and confirms previous experimental findings by Hong et al. [Phys. Rev. A 108, 013318 (2023)].