Vortex stability of interacting Bose-Einstein condensates confined in anisotropic harmonic traps

TL;DR

This paper investigates the stability of vortex states in rotating Bose-Einstein condensates confined in anisotropic harmonic traps, revealing how trap anisotropy and atom number influence vortex stability and critical rotation frequencies.

Contribution

It provides a numerical analysis of vortex stability in anisotropic traps, including critical rotation frequencies and the relationship with bound core states, which is a novel exploration.

Findings

Vortex stability depends on trap anisotropy and atom number.

Displaced vortices can have long lifetimes in large condensates.

Critical rotation frequencies vary with trap shape and particle number.

Abstract

Vortex states of weakly-interacting Bose-Einstein condensates confined in three-dimensional rotating harmonic traps are investigated numerically at zero temperature. The ground state in the rotating frame is obtained by propagating the Gross-Pitaevskii equation for the condensate in imaginary time. The total energies between states with and without a vortex are compared, yielding critical rotation frequencies that depend on the anisotropy of the trap and the number of atoms. Vortices displaced from the center of nonrotating traps are found to have long lifetimes for sufficiently large numbers of atoms. The relationship between vortex stability and bound core states is explored.