Kibble-Zurek mechanism in a trapped ferromagnetic Bose-Einstein condensate

TL;DR

This paper investigates the formation of spin vortices during magnetic phase transitions in a trapped spin-1 Bose-Einstein condensate, demonstrating the Kibble-Zurek mechanism's relevance in inhomogeneous systems through mean-field theory analysis.

Contribution

It shows that the Kibble-Zurek mechanism occurs in inhomogeneous trapped condensates during rapid quenches, with detailed analysis of spatial variations and trap configurations.

Findings

Kibble-Zurek phenomena emerge in inhomogeneous BECs during fast quenches.

Slow quenches cause magnetized regions to expand, suppressing vortex formation.

Trap modifications influence vortex dynamics and phase transition behavior.

Abstract

Spontaneous spin vortex formation in the magnetic phase transition of a trapped spin-1 Bose-Einstein condensate is investigated using mean-field theory. In a harmonic trapping potential, an inhomogeneous atomic density leads to spatial variations of the critical point, magnetization time scale, and spin correlation length. The Kibble-Zurek phenomena are shown to emerge even in such inhomogeneous systems, when the quench of the quadratic Zeeman energy is fast enough. For slow quench, the magnetized region gradually expands from the center of the trap pushing out spin vortices, which hinders the Kibble-Zurek mechanism from occurring. A harmonic trap with a plug potential is also taken into account.