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Bogoliubov-Cerenkov radiation in a Bose-Einstein condensate flowing against an obstacle

I. Carusotto·S. X. Hu·L. A. Collins·A. Smerzi
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Abstract

We study the density modulation that appears in a Bose-Einstein condensate flowing with supersonic velocity against an obstacle. The experimental density profiles observed at JILA are reproduced by a numerical integration of the Gross-Pitaevskii equation and then interpreted in terms of Cerenkov emission of Bogoliubov excitations by the defect. The phonon and the single-particle regions of the Bogoliubov spectrum are respectively responsible for a conical wavefront and a fan-shaped series of precursors.

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I. Carusotto, S. X. Hu, L. A. Collins, A. Smerzi. 2006-12-05. Bogoliubov-Cerenkov radiation in a Bose-Einstein condensate flowing against an obstacle. https://doi.org/10.1103/physrevlett.97.260403

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