Off-axis Vortex in a Rotating Dipolar Bose-Einstein Condensation

TL;DR

This paper analyzes the behavior of off-axis vortices in rotating dipolar Bose-Einstein condensates, deriving analytic and numerical results on how dipolar interactions influence vortex dynamics and stability in different trap geometries.

Contribution

It provides the first analytic and numerical analysis of off-axis vortex behavior in dipolar BECs, highlighting the effects of dipolar interactions on vortex precession and metastability.

Findings

Dipolar interactions increase (decrease) energy as vortex moves outward in oblate (prolate) traps.

Dipolar effects lower (raise) vortex precession velocity in oblate (prolate) traps.

Dipolar interactions influence the onset of metastability in vortex configurations.

Abstract

We consider a singly quantized off-axis straight vortex in a rotating dipolar ultracold gas in the Thomas-Fermi (TF) regime. We derive analytic results for small displacements and perform numerical calculations for large displacement within the TF regime. We show that the dipolar interaction energy increases (decreases) as the vortex moves from the trap center to the edge in an oblate (a prolate) trap. We find that for an oblate (a prolate) trap, the effect of the dipole-dipole interaction is to lower (raise) both the precession velocity of an off-center straight vortex line and the angular velocity representing the onset of metastability.