title: Kibble-Zurek mechanism in a trapped ferromagnetic Bose-Einstein condensate.
abstract: Spontaneous spin vortex formation in a magnetic phase transition of a trapped spin-1 Bose-Einstein condensate is investigated based on mean-field theory. In a harmonic trapping potential, an inhomogeneous atomic density leads to spatial variations of the critical point, magnetization time, and spin correlation length. The Kibble-Zurek phenomena are shown to emerge even in such inhomogeneous spinor condensates, 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. The case of a toroidal trapping potential is also discussed.
authors.affiliation: Department of Engineering Science, University of Electro-Communications, Tokyo 182-8585, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Saito
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Masahito
authors.initials: M
authors.lastname: Ueda
mesh_terms: D003198:Computer Simulation; D060526:Magnetic Fields; D008956:Models, Chemical; D008958:Models, Molecular; D044367:Phase Transition