Measuring the disorder of vortex lattices in a Bose-Einstein condensate

Abstract

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Evolution of large-scale flow from turbulence in a two-dimensional superfluid

“…We use the 'blob detection' algorithm described by Rakonjac et al [40] to obtain an initial estimate of the locations of vortices from the optical density image. Due to the turbulent nature of our vortex distributions, the algorithm is not as robust as the application in vortex lattices; the presence of sound waves and vortex dipole pairs too close together to distinguish can lead to both false positive and false negative detections, respectively.…”

Topological defect dynamics of vortex lattices in Bose-Einstein condensates

“…The characterization of perturbed lattices put forward by us complements the recent work of Rakonjac et al [23], where the authors determine the disorder present in a vortex lattice in a BEC by comparing the ratio of the standard deviation of nearest neighbor distances to the mean distance. Here we extend the available tools by using orientational correlations, Delaunay triangulation for topological defect detection, and by introducing a method to controllably engineer lattice defects through phase imprinting.…”

“…For example, applying a kicked potential with a spatial geometry similar to the vortex lattice was shown to create transient superlattice structures in the density [22]. Quantifying the disorder of vortex lattices has recently become an active topic of interest [23,24]. These topics are particularly useful as they can allow the study of quantum turbulence in highly controllable systems [25][26][27].…”

Spin-Orbit-Coupled Interferometry with Ring-Trapped Bose-Einstein Condensates

“…Gravity is taken to act in the z direction and does not alter the symmetry, and so we do not consider it further. In our numerics we consider experimental parameters comparable to those described in [42,43], however, for faster numerics, we take the radial trapping frequency to be ω ⊥ = 2π × 80 Hz, the major radius of the ring to be R 0 = 5a ⊥ = 6.02 µm, and the number of 87 Rb atoms to be N = 10 4 .…”