Deterministic creation, pinning, and manipulation of quantized vortices in a Bose-Einstein condensate

TL;DR

This paper demonstrates a method to deterministically create, pin, and manipulate pairs of quantized vortices in a Bose-Einstein condensate using focused laser beams, enabling precise control of vortex arrangements.

Contribution

The authors introduce a novel technique employing laser beams to generate and control vortices in a BEC, allowing for deterministic vortex placement and movement.

Findings

Vortices are created by moving laser beams within the BEC.

Vortices can be pinned to laser beam positions.

Vortices are manipulable by translating the laser beams.

Abstract

We experimentally and numerically demonstrate deterministic creation and manipulation of a pair of oppositely charged singly quantized vortices in a highly oblate Bose-Einstein condensate (BEC). Two identical blue-detuned, focused Gaussian laser beams that pierce the BEC serve as repulsive obstacles for the superfluid atomic gas; by controlling the positions of the beams within the plane of the BEC, superfluid flow is deterministically established around each beam such that two vortices of opposite circulation are generated by the motion of the beams, with each vortex pinned to the \emph{in situ} position of a laser beam. We study the vortex creation process, and show that the vortices can be moved about within the BEC by translating the positions of the laser beams. This technique can serve as a building block in future experimental techniques to create, on-demand, deterministic arrangements of few or many vortices within a BEC for precise studies of vortex dynamics and vortex interactions.