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arXiv · 1710.05800

A rapidly expanding Bose-Einstein condensate: an expanding universe in the lab

S. Eckel·A. Kumar·T. Jacobson·I. B. Spielman·G. K. Campbell
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Abstract

We study the dynamics of a supersonically expanding ring-shaped Bose-Einstein condensate both experimentally and theoretically. The expansion redshifts long-wavelength excitations, as in an expanding universe. After expansion, energy in the radial mode leads to the production of bulk topological excitations -- solitons and vortices -- driving the production of a large number of azimuthal phonons and, at late times, causing stochastic persistent currents. These complex nonlinear dynamics, fueled by the energy stored coherently in one mode, are reminiscent of a type of "preheating" that may have taken place at the end of inflation.

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S. Eckel, A. Kumar, T. Jacobson, I. B. Spielman, G. K. Campbell. 2018-04-20. A rapidly expanding Bose-Einstein condensate: an expanding universe in the lab. https://doi.org/10.1103/physrevx.8.021021

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