title: Double universality of a quantum phase transition in spinor condensates: modification of the Kibble-Żurek mechanism by a conservation law.
abstract: We consider a phase transition from an antiferromagnetic to a phase separated ground state in a spin-1 Bose-Einstein condensate of ultracold atoms. We demonstrate the occurrence of two scaling laws, for the number of spin domain seeds just after the phase transition, and for the number of spin domains in the final, stable configuration. Only the first scaling can be explained by the standard Kibble-Żurek mechanism. We explain the occurrence of two scaling laws by a model including postselection of spin domains due to the conservation of condensate magnetization.
authors.affiliation: Instytut Fizyki PAN, Aleja Lotników 32/46, 02-668 Warsaw, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Świsłocki
authors.affiliation: Instytut Fizyki PAN, Aleja Lotników 32/46, 02-668 Warsaw, Poland.
authors.forename: Emilia
authors.initials: E
authors.lastname: Witkowska
authors.affiliation: Instytut Fizyki Uniwersytetu Jagiellońskiego, ul. Reymonta 4, 30-059 Kraków, Poland.
authors.forename: Jacek
authors.initials: J
authors.lastname: Dziarmaga
authors.affiliation: Instytut Fizyki PAN, Aleja Lotników 32/46, 02-668 Warsaw, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Matuszewski