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arXiv · 1301.1991

Stability Spectroscopy of Rotons in a Dipolar Bose Gas

John P. Corson·Ryan M. Wilson·John L. Bohn
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Abstract

We study the stability of a quasi-one-dimensional dipolar Bose-Einstein condensate (dBEC) that is perturbed by a weak lattice potential along its axis. Our numerical simulations demonstrate that systems exhibiting a roton-maxon structure destabilize readily when the lattice wavelength equals either half the roton wavelength or a low roton subharmonic. We apply perturbation theory to the Gross-Pitaevskii and Bogoliubov de Gennes equations to illustrate the mechanisms behind the instability threshold. The features of our stability diagram may be used as a direct measurement of the roton wavelength for quasi-one-dimensional geometries.

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John P. Corson, Ryan M. Wilson, John L. Bohn. 2013-01-09. Stability Spectroscopy of Rotons in a Dipolar Bose Gas. https://doi.org/10.1103/physreva.87.051605

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