In situ imaging of vortices in Bose-Einstein condensates

TL;DR

This paper introduces a new dark-field imaging technique for in situ detection of vortex distributions in Bose-Einstein condensates, enabling real-time observation of vortex dynamics without expanding the condensate.

Contribution

The study demonstrates a novel in situ imaging method for vortex detection in BECs, allowing real-time vortex dynamics analysis in single-component condensates.

Findings

Successful generation of vortex lattices in BECs via rotation

Vortex core diameters measured around 400 nm

Vortex cores separated by approximately 9 micrometers

Abstract

Laboratory observations of vortex dynamics in Bose-Einstein condensates (BECs) are essential for determination of many aspects of superfluid dynamics in these systems. We present a novel application of dark-field imaging that enables \texttt{\it in situ} detection of two-dimensional vortex distributions in single-component BECs, a step towards real-time measurements of complex two-dimensional vortex dynamics within a single BEC. By rotating a $^{87}$Rb BEC in a magnetic trap, we generate a triangular lattice of vortex cores in the BEC, with core diameters on the order of 400 nm and cores separated by approximately 9 $\mu$m. We have experimentally confirmed that the positions of the vortex cores can be determined without the need for ballistic expansion of the BEC.