Topological stirring of two-dimensional atomic Bose-Einstein condensates

TL;DR

This paper explores how different topological stirring protocols affect vortex distribution in two-dimensional Bose-Einstein condensates, revealing insights into quantum turbulence and vortex dynamics.

Contribution

It introduces the application of Pseudo-Anosov topological stirring protocols to quantum fluids, comparing their effectiveness with finite-order protocols in vortex mixing.

Findings

Pseudo-Anosov protocols produce more chaotic vortex distributions.

Finite-order protocols result in more clustered vortices.

Implications for understanding quantum turbulence dynamics.

Abstract

We stir vortices into a trapped quasi two-dimensional atomic Bose-Einstein condensate by moving three laser stirrers. We apply stirring protocols introduced by Boyland et. al. (2000) that efficiently build in topological chaos in classical fluids and are classified as Pseudo-Anosov stirring protocols. These are compared to their inefficient mixing counterparts, finite-order stirring protocols. We investigate if inefficient stirring protocols result in a more clustered distribution of vortices. The efficiency with which vortices are 'mixed' or distributed in a condensate is important for investigating dynamics of continuously forced quantum turbulence and the existence of the inverse cascade in turbulent two-dimensional superfluids.