Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

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

Published

Author(s)

Stephen P. Eckel, Avinash Kumar, Theodore Jacobson, Ian B. Spielman, Gretchen K. Campbell

Abstract

We study the dynamics of a supersonically expanding Bose-Einstein ring condensate both experimentally and theoretically using simulations. Such expansion shows a redshift of long-wavelength excitations, similar to those seen in the standard cosmological picture of an expanding universe. After the expansion ceases, we then observe the creation of large numbers of azimuthal phonon excitations in the ring and topological excitations in the form of persistent currents. The process through which these excitations are produced involves short length scales where the Bogolyubov spectrum becomes non-linear (i.e., Lorentz symmetry fails). Bulk topological excitations -- solitons and vortices -- drive the production the azimuthal phonons and, at late times, cause stochastic persistent currents.
Citation
Physical Review X
Volume
8

Keywords

Bose-Einstein condensation, cosmology, phonons, superfluidity, ultracold atoms, solitons, vortices

Citation

Eckel, S. , Kumar, A. , Jacobson, T. , Spielman, I. and Campbell, G. (2018), A supersonically expanding Bose-Einstein condensate: an expanding universe in the lab, Physical Review X, [online], https://doi.org/10.1103/PhysRevX.8.021021 (Accessed August 12, 2022)
Created April 19, 2018, Updated November 10, 2018