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arXiv · 1803.05410

Effective non-linear spinor dynamics in a spin-1 Bose-Einstein condensate

Alessandro Michelangeli·Alessandro Olgiati
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Abstract

We derive from first principles the experimentally observed effective dynamics of a spinor Bose gas initially prepared as a Bose-Einstein condensate and then left free to expand ballistically. In spinor condensates, which represent one of the recent frontiers in the manipulation of ultra-cold atoms, particles interact with a two-body spatial interaction and a spin-spin interaction. The effective dynamics is governed by a system of coupled semi-linear Schrödinger equations: we recover this system, in the sense of marginals in the limit of infinitely many particles, with a mean-field re-scaling of the many-body Hamiltonian. When the resulting control of the dynamical persistence of condensation is quantified with the parameters of modern observations, we obtain a bound that remains quite accurate for the whole typical duration of the experiment.

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Alessandro Michelangeli, Alessandro Olgiati. 2018-09-03. Effective non-linear spinor dynamics in a spin-1 Bose-Einstein condensate. https://doi.org/10.1088/1751-8121%2Faadbc2

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