Vortex structure in spinor F=2 Bose-Einstein condensates

TL;DR

This paper investigates vortex structures in spinor F=2 Bose-Einstein condensates, analyzing phase transitions, energy states, and novel vortex types through numerical and variational methods.

Contribution

It provides a detailed analysis of vortex solutions and phase transitions in F=2 condensates, including the discovery of two new vortex structures.

Findings

Ground state depends on magnetization and interaction channels.

Particles condense into one, two, or three hyperfine states.

Two novel vortex structures are identified.

Abstract

Extended Gross-Pitaevskii equations for the rotating F=2 condensate in a harmonic trap are solved both numerically and variationally using trial functions for each component of the wave function. Axially-symmetric vortex solutions are analyzed and energies of polar and cyclic states are calculated. The equilibrium transitions between different phases with changing of the magnetization are studied. We show that at high magnetization the ground state of the system is determined by interaction in "density" channel, and at low magnetization spin interactions play a dominant role. Although there are five hyperfine states, all the particles are always condensed in one, two or three states. Two novel types of vortex structures are also discussed.