Parametric Excitation of a Bose-Einstein Condensate: From Faraday Waves to Granulation

Understand

We explore, both experimentally and theoretically, the response of an elongated Bose-Einstein condensate to modulated interactions.

• We identify two distinct regimes differing in modulation frequency and modulation strength.
• Longitudinal surface waves are generated either resonantly or parametrically for modulation frequencies near the radial trap frequency or twice the trap frequency, respectively.
• The dispersion of these waves, the latter being a Faraday wave, is well-reproduced by a mean-field theory that accounts for the 3D nature of the elongated condensate.