We investigate the structure and collective modes of a planar surface of a trapped Bose-Einstein condensed gas at zero temperature. In the long-wavelength limit we find a mode similar to the gravity wave on the surface of a fluid with the frequency [Formula Presented] and the wave number q related by [Formula Presented] Here F is the force due to the confining potential at the surface and m is the particle mass. At shorter wavelengths we use a variational approach and find corrections to [Formula Presented] of order [Formula Presented] We demonstrate the usefulness of the concept of an effective surface tension for describing both static and dynamic properties of condensed atomic clouds.
|Number of pages||6|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|Publication status||Published - 1999|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics