A quenched spinor Bose-Einstein Condensate: From U(1) to U(1)xZ2

Published

March 25, 2014

Author(s)

Ian B. Spielman, Subhadeep De, Daniel Campbell, Ryan Price, Andika Putra, Brandon Anderson

Abstract

We explore the time evolution of quasi-1D two component Bose-Einstein condensates (BEC's) following a quench from a spin polarized gas with a ${\rm U}(1)$ order parameter to a two component condensate with a ${\rm U}(1)\shorttimes{\rm Z}_2$ order parameter. These spin components have a propensity to phase separate: are immiscible. A spatially uniform mixture of these spins is dynamically unstable, and rapidly amplifies any quantum or pre-existing classical spin fluctuations. This coherent growth process drives the formation of numerous spin polarized domains, which are far from the system's ground state. At much longer times, these domains grow in size, coarsening, as the system approaches equilibrium. Remarkably, this system can be understood in terms of a single ${\rm U}(1)$ order parameter describing a collapsing attractive BEC. This experimentally observed evolution is fully consistent with our stochastic-projected Gross-Pitaevskii calculation at all times.

Citation

Physical Review Letters

Pub Type

Journals

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DOI Link

Keywords

Bose-Einstein Condensate, coarsening, collapse, domains, spinor

Citation

Spielman, I. , De, S. , Campbell, D. , Price, R. , Putra, A. and Anderson, B. (2014), A quenched spinor Bose-Einstein Condensate: From U(1) to U(1)xZ₂, Physical Review Letters, [online], https://doi.org/10.1103/PhysRevA.89.033631 (Accessed October 8, 2025)