Gauge-potential-induced rotation of spin-orbit-coupled Bose-Einstein condensates

TL;DR

This paper introduces a novel method to rotate spin-orbit-coupled Bose-Einstein condensates using gauge potentials and magnetic fields, leading to unique vortex structures distinct from traditional techniques.

Contribution

It demonstrates a new approach to induce rotation in BECs via gauge potentials, resulting in vortex nucleation and complex vortex configurations, different from conventional stirring or laser methods.

Findings

Gauge angular momentum induces vortex nucleation.

Discovery of half-integer giant vortices in weakly interacting regimes.

Prediction of coaxial annular vortex arrays under strong interactions.

Abstract

We demonstrate that a spin-orbit-coupled Bose-Einstein condensate can be effectively rotated by adding a real magnetic field to inputting gauge angular momentum, which is distinctly different from the traditional ways of rotation by stirring or Raman laser dressing to inputting canonical angular momentum. The gauge angular momentum is accompanied by the spontaneous generation of equal and opposite canonical angular momentum in the ground states, and it leads to the nucleation of quantized vortices. We explain this by indicating that the effective rotation with the vortex nucleation results from the effective magnetic flux induced by the gauge potential, which is essentially different from the previous scheme of creating vortices by synthetic magnetic fields. In the weakly interacting regime, symmetrically placed domains separated by vortex lines as well as half-integer giant vortices are discovered. With relatively strong interatomic interaction, we predict a structure of coaxially arranged annular vortex arrays, which is in stark contrast to the familiar Abrikosov vortex lattice. The developed way of rotation may be extended to a more general gauge system.