Topological vortex formation in a Bose-Einstein condensate

TL;DR

This paper demonstrates the creation of vortices with quantized circulation in a Bose-Einstein condensate through topological phase imprinting, revealing specific angular momentum states depending on hyperfine levels.

Contribution

It introduces a method to generate and analyze topological vortices in BECs using magnetic field inversion and surface wave spectroscopy.

Findings

Vortices with quantized circulation were successfully imprinted.

The angular momentum per particle was measured as 2ħ or 4ħ.

The vortex states depend on the hyperfine state of the condensate.

Abstract

Vortices were imprinted in a Bose-Einstein condensate using topological phases. Sodium condensates held in a Ioffe-Pritchard magnetic trap were transformed from a non-rotating state to one with quantized circulation by adiabatically inverting the magnetic bias field along the trap axis. Using surface wave spectroscopy, the axial angular momentum per particle of the vortex states was found to be consistent with $2\hbar$ or $4\hbar$, depending on the hyperfine state of the condensate.