Non classical velocity statistics in a turbulent atomic Bose Einstein condensate

TL;DR

This paper demonstrates that turbulent velocity statistics in atomic Bose-Einstein condensates exhibit non-Gaussian power-law tails, similar to superfluid helium, indicating a fundamental quantum fluid property.

Contribution

The study provides the first direct computation of turbulent velocity fields in atomic BECs, revealing non-classical statistics and analyzing vortex tangle decay.

Findings

Velocity components show non-Gaussian power-law tails.

Quantum turbulence shares statistical features with superfluid helium.

Vortex tangle decay dynamics are characterized.

Abstract

In a recent experiment Paoletti et al (Phys. Rev. Lett. 101, 154501, 2008) monitored the motion of tracer particles in turbulent superfluid helium and inferred that the velocity components do not obey the Gaussian statistics observed in ordinary turbulence. Motivated by their experiment, we create a small turbulent state in an atomic Bose-Einstein condensate, which enables us to compute directly the velocity field, and we find similar non-classical power-law tails. Our result thus suggests that non-Gaussian turbulent velocity statistics describe a fundamental property of quantum fluids. We also track the decay of the vortex tangle in the presence of the thermal cloud.