Vortices in a rotating Bose-Einstein condensate under extreme elongation in a harmonic plus quartic trap

TL;DR

This paper investigates the behavior of rapidly rotating Bose-Einstein condensates in an elongated trap with a quartic potential, revealing stable vortex lattices and complex transitions influenced by rotation speed and interactions.

Contribution

It introduces a study of vortex dynamics in a 2D anisotropic harmonic plus quartic trap, highlighting stability at high rotation speeds and vortex lattice transitions without prior focus on such extreme elongation.

Findings

Vortex lattices form even without repulsive interactions.

System remains stable at rotation speeds exceeding the harmonic trap frequency.

Vortex lattice transitions occur as a function of rotation speed, eventually vanishing at high speeds.

Abstract

The behaviors of a rapid rotating Bose-Einstein condensate under extreme elongation in a 2D anisotropic harmonic plus quartic trap are investigated. Due to the quartic trap, the system remains stable at high rotating velocity, $\Omega\geq \omega_\perp$ ($\omega_\perp$ is the radial harmonic trap frequency), and vortex lattices form even in the absence of the repulsive s-wave interaction ($g$). When $g$ is present, the interplay between $g$ and the quartic trap potential can lead to rich vortex lattice transition states as a function of $\Omega$, to which vortex lattices vanish eventually at some higher $\Omega$.